Here's a replacement part that should allow you to repair or replace the original part with the same component:
"From: Gitlow 1/7/2006 1:46 am
To: 64PA30 (9 of 15)
6061.9 in reply to 6061.7
Ouch. I paid Allied Electronics $22.30 per rheostat when I bought a few back in October 2000. The part is now $25.84 from the same source. There are some other parts involved in the assembly, but they're not the ones that typically fail. If it was truly the rheostat that Princeton charged you for, that's outrageous.
Allied is available at: http://www.alliedelec.com
Run a search there for Ohmite Rheostat RHS10R to find the part.
Like John, I thought of increasing the wattage capabilities of the part to find something more longlasting, and there were several choices, but I worried about the size issues and figured that at $25/rheostat, it wasn't a big deal."
francois