The $200 Rick charges is all inclusive of and duties/fees, no sales tax. I've bought a few amps from him and this is the going rate unless you're buying a couple at a time.
Sounds like the amp is being completely rebuilt, not sure why folks on the other thread are losing their minds. Rick is an honest guy and builds a hell of an amp. If you didn't buy him and got it second hand you're kinda at the mercy of how many other irons he has in the fire and how bad you need the amp fixed is my guess. I had a used MC1 50w years ago that i sent him as it had an issue with a cap or something. price was about $500 to fix, update and ship, but wasn't doing a complete rebuild like yours.