Fisher brand was bought by Sanyo in the 1970's so yours will be made by Sanyo (who have recently been taken over by Matsushita/Panasonic).
Personally, I wouldn't bother to repair hifi of that provenance -- particularly if it's something complex like a multi-disc player. If just the amplifer/receiver unit, those could be tackled by a local repair man.
If the speakers were supplied by Fisher/Sanyo, they were pretty awful. Perhaps take this as an opportunity to by a 'real' hifi -- ie not from a chain store in a mall but from a small specialist dealer that doesn't only sell Japanese brands.