It's much easier to find a used Rock 7 in Great Britain ( 240V 50hz motor ) than the US and at a much better price. I just bought one for 1000 Pounds plus 50 pounds shipping ( about $1650 ) including an Audio Origami RB251 arm. It's easy to run a 240V 50Hz turntable in the US by buying a good quality 12V to 240v 50hz power inverter ( about $280 ) and a good quality 12V linear power supply. The combo puts out a really stable 240V 50hz output and allows you to use 240v 50hz motor controllers such as the Heed Audio Orbit 2 which requires no mods to the turntable motor at all.
look on HiFi Wigwam in the classifieds forum. They come up once in a while.
look on HiFi Wigwam in the classifieds forum. They come up once in a while.