First off, Nothing wrong with MOST repros now of days. Some of the stuff you buy at LMC is still tooled wrong and body lines dont match up. For used stuff you may want to check out the classifieds section here, matter of fact Im selling and entire 71 front clip on there for $650. shipping would prob kill you though. As for used, if they arent rusted through out there or beat to hell, buy em... pay a little cash out and have a good body shop clean them up unless you know your way around the tools.
Also, this post should have been in the general forum... not the projects and builds
Good luck finding some parts brother...