I think it's an epiphone... maybe a lp-100? that's the only epi I know of that has 4 knobs and a bolt-on neck.

a serial number in the neck pocket would help, but it appears that if there was one, it was since scratched out. I'd think that any gibson/epiphone LP neck should fit it, or you can buy a block of wood from stewmac and grind it down to your own shape :cool: the switch between the knobs was probably an aftermarket addition and could be series/parallel or coil-tap.

I'd say you got a pretty good deal for only $5! heck, I'll buy it off you for 6... :D