I don't think the forums could handle all the costume assets in the game.
There are no words for what this community, and the friends I have made here mean to me. Please know that I care for all of you, yes, even you. If you Twitter, I'm MrThan. If you're Unleashed, I'm dumps. I'll try and get registered on the Titan Forums as well. Peace, and thanks for the best nine years anyone could ever ask for.
I don't know of one that just individual costume pieces but Here is a thread with a lot of costume.
"All right, they're on our left, they're on our right, they're in front of us, they're behind us...they can't get away this time"- Chesty Puller US Marine Corps
Is there a thread with images that show the costume pieces?