Actually rules for choas, standard power armor, imperial guard, and heck-even eldar were published in white dwarf over the years. Some of these weapons you list had official rules and considering that 4E was basically the same rule set they should fit in very well. Here's specific excerpts from the original rules (Pm for full accounting
Bolter:
The standard bolter rolls 2 dice at targets 6 squares or closer and 1 die at targets over 6 squares. They gain sustained fire and jam as in the Storm Bolter rules. Note, they won't jam when firing over 6 squares on Overwatch.
BOLT PISTOL
Used by: Space Marines , Imperial Guardsmen,
Orks, Chaos Marines,
Type: Ranged Weapon and Close Assault
Weapon
Cost to Fire: 1 AP Hit Dice: 1 To Hit: 6
Bolt pistols have a shorter range than bolters but their
compact size allows them to be fired against close
combat opponents, so models with bolt pistols gain a
+1 close assault modifier against opponents in their
front or side squares. Bolt pistols get no sustained fire
bonuses.
BOLTER (or BOLT GUN)
Used by: Space Marines, Chaos Marines
Type: Ranged Weapon
Cost to Fire: 1 AP Hit Dice: 1 To Hit: 6
Like storm bolters, bolters are capable of sustained fire
but their maximum bonus is lower. Stealer Hybrids with
bolters can be placed in overwatch but this reduces
their range from unlimited to 12 squares.
Sustained Fire Hit On
First shot 6
Second shot 5
Subsequent shots 4
Bolters and Overwatch
Bolters in overwatch roll one dice per shot, and kill on a
score of six. They have a much lower rate of fire than
storm bolters, so they do not jam in overwatch. The only
way the Marine can lose overwatch during the Stealer
turn is if the Marine suffers a close combat attack, or
moves or turns by spending command points.
HEAVY BOLTER
Used by: Space Marines, Chaos Marines
Type: Heavy Ranged Weapon
Cost to Fire: 2 APs Hit Dice: 2 To Hit: 6
As this is a much larger weapon than the standard bolter, models with heavy
bolters roll two dice and get improved bonuses for sustained fire. Move and
fire actions are not possible with heavy bolters but they can be put into
overwatch.
Sustained Fire Hit On
First shot 6
Second shot 5
Third shot 4
Subsequent shots 3
Flamer:
A combi-flamer may be fired once per mission as a flamer. This costs only 1 AP. Any models caught in the blast will survive on a 4+ rather than a 6+ as the flamer spouts less fuel and ignites a weaker conflagration than a Heavy Flamer. Where a hit from a Heay Flamer is necessary to complete mission objectives, a hit from a Flamer will not fulfill the objective. Broodlords are immune.
FLAMER (STANDARD)
Used by: Space Marines, Chaos Marines
Type: Ranged Weapon (w/ Area Effect)
Cost to Fire: 2 APs Hit Dice: 1 To Hit: 4 Ammo: 6
The ordinary flamer carried by Space Marines is a small, light
weapon. It is fired using either one or both hands and works in much
the same way as the heavy flamers carried by the Terminators in
Space Hulk. Almost all the rules given for the heavy flamer apply: the
flamer has six shots, a range each hit affects an entire board section
and blocks movement and LOS.
The main difference between the two sorts of flamer is that a
standard flamer is far less powerful: flamer hits kill Genestealers and
Blips on a score of 4 or more. However,
Marines in Powered Armor who’re accidentally hit by the blast are removed on a score of 2 or more, And Marines in
Terminator armor are killed on a score of 5. Flamer Marines carry one reload for their weapon. This reloading action
costs 4 APs and can be paid for either by the Marine’s own APs, CPs, or a combination of the two. The Marine player
loses any remaining shots in the flamer, and gets a new stack of flamer markers.
Melta:
Meltaguns fire bursts of superheated gas able to melt through bulkheads or vaporize flesh with ease. A combi-melta may be fired once per game as a meltagun. This costs 1 Ap. Any models and doors within 6 squares directly in front of the firing terminator are automatically destroyed. Broodlords have a 4+ save against death from a meltagun blast.
MELTA GUN
Used by: Space Marines, Chaos Marines, Imperials, Eldar
Type: Heavy Ranged Weapon (-1 AP to model)
Cost to Fire: 1 APs Hit Dice: 1 To Hit: 2
Because this gun is quite cumbersome, any model
using it only has 1 less AP than they would normally.
It has two shooting dice. The lack of both recoil and
recharging time allow the Melta Gun to get sustained
fire bonuses while moving and firing. A melta-gun
destroys Genestealers, Terminators and Doors on a
roll of 2 or better. A roll of 4 or better is needed to
destroy a bulkhead.
Plasma:
Plasmaguns fire superheated plasma bolts that explode on impact releasing the fury of a small sun. A combi-plasma may be fired once per game as a plasmagun. This costs 1 AP. The plasmagun rolls 2 dice at 6 squares and closer and 1 die over 6 squares. It destroys any models or doors on a 3+. Any Genestealers adjacent to a model or door destroyed by a plasmagun are caught in the plasma explosion and killed on a 5+. Broodlords have a 4+ save against death when hit by a plasmagun and are immune to splash damage.
Overheat! If doubles are scored while firing the plasmagun, the weapon overheats and may injure the wielder. Roll a D6. On a score of 1 the Terminator is slain. On a 2 or 3, the weapon melts and is destroyed and the Terminator may not shoot the bolter for the remainder of the game. On a 4-6 the gases are vented safely and no harm comes to the Terminator.
PLASMA GUNS and PISTOLS
Used by: Hybrids, Imperials, Eldar
Type: Heavy Ranged Weapon (w/ Area Effect)
Cost to Fire: 2 APs Hit Dice: 1 To Hit: 2
As soon as a plasma gun or plasma pistol has been fired, place
a plasma weapon counter beside the model, with the fired side
face up. At the start of that model’s next turn, flip the counter
over so that the recharging side is now face up. Then, at the
start of that model’s next turn (ie the second turn after the gun
was fired), the counter should be removed. While a model has a
counter beside it, on either the fired or recharging side, it cannot
fire its plasma weapon  this means plasma guns and pistols
can only be fired once every two turns. Models with plasma guns
and plasma pistols can’t be placed in overwatch.
HEAVY PLASMA GUN
Before a heavy plasma gun is fired, the player must declare
whether rapid fire or maximal fire is being used.
Rapid Fire: because this option only uses a small amount of the
heavy plasma gun’s vast energy reserves, no plasma weapon
counter is placed beside the model when it fires. It can fire again
in the same turn in either mode. Maximal Fire: this option
releases the weapon’s energy in a single all-out burst affecting
all the models and features in one section. The heavy plasma
gun has unlimited range but at least one square in the target
section must be within the firer’s LOS. Once the heavy plasma
gun has been fired on maximal fire, place a plasma weapon
counter beside the model as described above. Models with
heavy plasma guns cannot be placed in overwatch and cannot
move and fire.
Reaper Autocannon:
Reaper Autocannons are a twin-linked autocannon designed to be carried by terminators that fire large calibur projectiles at a terrifying rate and volume. They are relics of a bygone technological age and are meticulously maintained by their users. Despite their withering rate of fire, Reapers are very reliable and not prone to malfunction as the more modern Assault Cannon.
Firing the Reaper costs 1 AP. When firing the Reaper, roll two dice scoring a hit on 4+. The Reaper has the same number of shots as the Assault Cannon and costs the same number or AP to reload. The Reaper will not overheat and explode as the Assault Cannon could.
AUTOCANNON
Used by: Genestealer Hybrids, Chaos Marines
Type: Ranged Heavy Weapon (must stand still to fire)
Cost to Fire: 1 AP Hit Dice: 1 To Hit: 4
The autocannon has such hefty recoil that the firer must
brace himself firmly to take the shock. Thus, the
autocannon can’t be used for overwatch or for move
and fire actions. Within the confines of a space hulk,
the autocannon has an unlimited range, but is
particularly effective at closer range. It costs 1 AP to
fire an autocannon, and it has one hit die. At a range of
12 or less, a roll of 4 or better is needed to kill a
Terminator, and a roll of a 3 to kill a Genestealer or Blip.
At greater ranges, a 5 is needed to kill a Terminator.
Sustained fire bonuses apply, but a roll of 1 is always a
mi s s
Power/Chain/Shock Weapons:
Chaos Terminators come armed with a wide array of close combat weaponry depending on the bearer's taste. Although potent weapons all, they lack the defensive and offensive power of a Power Fist or Power Claw. When fighting in close combat with a power weapon, roll a single die as normal but ties count as a Genestealer victory.
CHAINSWORD
Used by: Eldar, Harlequins
Type: Close Assault Weapon (can Parry)
Cost to Fire: 1 AP CA Dice: 1 CAB: +1
The chainsword is a cross between a chainsaw and the
power sword that’s commonly used by Terminator
Captains. Both swords give the user the chance to parry
by making the opponent re-roll one die used in the
attack. Because a Harlequin will always be facing the
opponent the Harlequin will always be able to parry an
attack. Both players roll dice as normal for the attack,
but then the Harlequin player can ask the Genestealer
player to re-roll one of the three dice. This roll then
counts even if it is higher than the first roll. A Harlequin
armed with a chainsword gains a +1 bonus in close
assault.
POWER AXE
Used by: Eldar, Harlequins
Type: Close Assault Weapon (can break doors for 2 APs)
Cost to Attack: 1 AP CA Dice: 1 CAB: +1
The power axe is a large bladed weapon with a
powered edge. It is used in close combat with similar
effect to a power sword, although its heavier bulk
prevents the user from parrying. It can be used to break
through doors and bulkheads. The Harlequin armed
with a power axe gains a +1 bonus in close assault.
The power axe can also be employed using heavy
chops to literally break the door down. This costs 1 AP
for a door, and 2 AP for a bulkhead. No roll is needed,
to destroy doors with a power axe.
