You might try Greybeard Outdoors
www.go2gbo.com They have a Contender Classified forum that you might try, Just sign up and post a WTB of what you want.
It might be worth mentioning that the TC barrels all have a standard .308 twist (1/10") that might not stabilize the heavier bullets at subsonic speeds. You might consider ordering the barrel from Match Grade Maching and get the length and twist you want.