Smoke_Eater, welcome to the boards first off. Go check on www.ebay.com and look for cars in your area, also look in www.collectorcartraderonline.com
www.hotrodhotline.com has cars for sale as well.
The best thing to do I think is go and hang out with some older guys at hot rod meets, shows, etc in your area and talk to them and tell them what you are looking for. Most likely they have what you need. And I do mean MOST likely. I wen't to the local rod meet one night and a guy I know asked for a Vette rear end 3 minutes after we got outta the car and the first guy we asked knew where to get one real cheap.
I don't know your area or nothing so can't tell you where one is around you but hopefully those sites and the info will help you out.

Shawn-