Hi!
You could scratch build an armor 
I like to do that! If you're interested in that, just reply to this, and I can give you a somewhat detailed explanation. There is a guy on youtube who builds fantastic iron man costumes. I've followed his method on an iron man, and now I'm working on a mandalorian myself using the same method, as it's applicable to any armor really. I could post some links if you want 
Oh, and just for the record, what kind of ARC? Clone Wars Style? Phase I or II from the movies? It's kind of important if you're gonna build, since getting the templates for certain variations is hard.....you might have posted that though....I don't read too thoroughlly

-Ghost