I'll ad, I would network and find a guy that deals locally with swap meets. There is a guy near me that has tons of Camaro only parts. He goes to several swaps and sets up. If I need a part, I can always use him as a "go to" for factory stuff. He usually is cheaper than ePay and lets you know if it is repro or not.
Once you establish a relationship, it is easier to just call for your needs. Make sure the guy is not dishonest (ask around). He may even trade or buy your extras out right. The guy I know has found several desirable parts I can recall. He even bought an NOS endura bumper jack rest for $5 once. rosewood wheels for $25. Of course he knows their value, but original beats repro any day IMO.