Playing Devil's Advocate: Realize that the S1 is pretty much non-repairable. It probably could be fixed but most (if not all) repairs will cost more than the camera is worth.

JSPhoto's recommendations are good places to deal with and I've heard good things about KEH.com but never bought anything there personally. Calumetphoto.com is another good place. It's just a matter of someone having one in stock. When this camera came out, being an early DSLR, there weren't anywhere near as many made as the D50, etc so you may have to be patient for one to come up on the used market.

There are a few others out there like the original Nikon D1 or some of the older Kodak DSLR's (some were Canon and some Nikon) but I think I'd go with the S1 over any of these - for the record I'd hold out for a D50 myself, but I understand about the money.