ME and my friend are planning on making costumes for events and such (mainly for halloween

) next year and are planning on starting early. I'm planning on being commisar (similar to commisar cain in this pic:
http://www.spuler.us/40k/large/cains_last_stand.jpg) and he is gonna be a cadian guardsmen. We are going to start building probably this weekend and are going to get stuff together. here is the basic plan.
Commisar:
Hat: borroing my friends, he already has a very similar hat.
Jacket: Basic black suit blazer (not sure what im doing about the shoulder pad thingies)
Vest: black vest, gonna pick up one similar at goodwill for a couple bucks and then do the gold embroidery and such pretty simply on my own
Sash: just some plain red cloth.
Gloves: Black welding gloves (im really thinking hard about changing that, i think i could do a better job on that one)
Pants: just some black dress pants
Bolt Pistol: i have a nerf gun that is perfect size and shape of a bolt pistol except for the clip which is an easy fix with cardboard and spray paint. (this nerf gun actually gave us the idea because we had a nerd rage when we realised that it looked like a bolt pistol)
Boots: black combat boots.
Chainsword: Making it around the base of the handle which will be a round piece of wood. we will then make a cardboard cover for the blade and cardboard hand guard. not sure how to do the teeth of the chainsword though. suggestions please..
Guardsman:
Helmet: We have a military helmet from some past war. just gonna stick an imperial eagle on the front and paint it the proper color. (it should look similar to this but with a different color.
http://www.spatcave.com/warhammer2/DSC06028res.jpg)
Pants: just plain grey somewhat baggy pants
Shirt: long sleeve grey shirt
Boots: black combat boots.
Armour: this is where it gets difficult. we are planning on working with some card board to form the the chest piece. but i am also planning on making the rounded shoulders out of maybe foam of also cardboard. i will prolly paint them and then use fiber glass tape (similar to that used on the dreadnaught costume project
http://www.dakkadakka.com/dakkaforum/posts/list/270645.page) just to make it solid...
and suggestions on paint scheme for the guardsmen? we're thinking about using the scheme my friend has on his army:
http://www.dakkadakka.com/gallery/78252-.html?m=2
Suggestions are welcome, i would love to have any help i could get

thanks

may the emperor bless you with many sixes