Any assistance in a parts quest for a Maestro USS-1a

[dumbmonkey]

Hey y'all,
I seem to be in the wonderful position of attempting to repair a Maestro USS-1a and its footswitch for a friend of mine.  I've got the unit cleaned and working, but one of the slider pots is broken and needs replacement.  According to a schematic I found, the pot is a 50k audio taper, and from physical inspection, it is a CTS part with EF8133 printed on the side.  I measured the throw to be about 60mm.  I started checking out slide pots at Mouser, but before I got too involved with data sheets, I thought I might try on the forum to see if anyone had a junk unit around or knows some other place where I might get an actual pot or two from one of these dinosaurs.
Any assistance or advice would be greatly appreciated.
Thanks!
Chris