I have a 457 I'm sort of in the same boat with. I bought it for the cabinet only, assuming the machine was toast. It worked long enough for me to decide it was actually a pretty decent machine, and then the top gear went crunchburger.
I plan on going ahead & fixing it...it won't cost much, it'll "save" the machine, it'll be good practice, and it will prevent me from feeling guilty for tossing it. Of course, meanwhile, it's sitting on the floor waiting its turn on the table, doing its best to break a toe or two when I walk by... LOL But when I'm done I'll have a nicely functioning machine that I can hopefully find a good home for.