I know of an older CMB 67 that is still brand new in its box, owner is asking £200 for it - around $280. If you're interested, I can pass on the email of it's owner
I've got an old style Picco 67 disc rotor that sounds like it's right up your alley! It looks like it's never been run. Excellent pinch on it. Complete with venturi and exhaust throttle. I may be able to dig up some mounts and a pipe to go with it if you want.