Have a couple of these for sale:
Powerstat Variable Autotransformer ("Variac") Type 136
120 VAC 20 Ampere 1 Phase 50/60 ~
0-120 or 0-140 VAC out depending on wiring.
Used, good shape.
$115 each plus shipping.
http://img4.imageshack.us/img4/761/powerstat013yo.jpg
http://img4.imageshack.us/img4/7706/powerstat021xr.jpg