I have a 1970's snoopy watch that I received for my 7th birthday. I overwound it a week later and it stayed in a drawer for 20 years at my grandmother's house, as she had promised to send it back for repair.
My grandmother (the original purchaser of the watch) returned it to the manufacturer 20 years later and I now have a mint condition working watch. The cost of repair was minimal compared to the collectable & sentimental value of the watch now. My grandmother re-gifted me with the working watch on my 27th birthday. I am guessing your best bet would be to send it back to the manufacturer.
Bobbi.
July 2009