You can probably do it yourself, but take it slowly.
Make lost of diagrams as you go, adn if you've got a digital camera, take lots of close ups along the way. Print these out and add comments as soon as possible, just to jog your memory when the time comes to reassemble it (could be a while if you have to wait for belts to arrive).
I had to do this on an old Pioneer cassette deck (CTF2121, the one that's front loading but where the cassette sits horizontally) when I was quite new to this game (still at junior school). It was a swine, but it went back together in the end, and has only recently expired
Generally, professional repair is very expensive, and hard to come by. If money's no object, call up the pros. If you're patient and have the right kind of mind, I bet you could do it yourself.
Nick.