I have an 86ish Schwinn SuperSport that has 2 bent seat stays. One is a simple bend that can probably be bent back but I don't think I can ever get the other side straight. So...I'm thinking about replacing both the stays and maybe even putting some track dropouts in while I'm at it.
I'm not attached to the bike but I think it would be a good rider if I can do a decent job of fixing it. My main concern is finding the tubes and getting everything aligned correctly. I have an acetylene torch but was thinking of using mapp gas after reading about it here.
Use the oxy-ace torch, gets hotter and you can pinpoint the heat better. It's what the pros use. Use brass for the dropouts and pratice before putting heat to the actual frame in question. You can use a properly dished rear wheel to help with alignment. Also, learn how to do the string alignment check - check Sheldon Brown's web site if you don't know what I'm refering to. For the stays call Joe Bringheli (bringheli.com). Good guy.
Becareful buying/selling bike parts on-line. I learned the hard way. :(