I don't have an HPC gun, but I did disassemble a B&D screwdriver of the type they're made from, and got a good look at the electric motor, made by Johnson. Yesterday I received a flier in the mail from The Electronic Goldmine (
www.goldmine-elec.com), an outfit that sells surplus high tech electronic parts and assemblies. Unless I'm mistaken, their catalog number G13775 may be that exact same motor. The dimensions and electrical characteristics match. Best of all, they're selling them for 99 cents each, which is probably a tenth of what B&D sells them for, if you can get them.