used pan pots should be quite easy to get, they are leftovers when racking up channels. reach out to funky junk, i'm sure they'll have some.
but before that you could try to wash it out with ipa (alcohol, not ale), hold it upside down and work it, to see if that cleans out whatever gunk is in there.
then instantly relube. i had good results with both eml and caig fader lube. this sometimes works, but definitely not always. and make sure to take the pot out to do this!