I think that the only supplier is ToyEast out of somewhere in either China or Japan. I've ordered some stuff from them. They have really cheap parts, but this is usually canceled out by their shipping fees. Lots of cool stuff though.
www.toyeast.com
the exact adress of the Perfection motors is
http://www.toyeast.com/v2/prodlist.asp?catid=763
(look on the left sidebar for the other Perfection products).
-Micro