If you can find a motor in your local area and check it as suggested above then fine. Buying it from 'out of town' and you might be getting a 'pig in a poke' with the same or even more problems than you already have. Plus shipping.
I'd find a good local rebuilder and get a price baseline of what you have, and what it will cost to correct its problems. This will give you a good idea of what kind of dollars you can spend on a replacement.
