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It's old enough to be the "smooth stem" design.

I looked at some $7 ones on eBay...negative reviews...so I went ahead and bought an $18 one straight from Fender.
(probably still Chinese, but 100% 5-star reviews).

My soldering iron is cheap, and I'll have to look for my rosin core solder...or maybe just let my buddy solder it for me (who has a nice iron and knows where his stuff is).

Luckily, the pot is stuck in the turned-up-all-the-way position, so it works until I replace it.

Usually, what causes these to jam is wires inside breaking.

...' piece of crap...' only lasted 52 years...

Perhaps play (and act out) less Clash covers?

Yes, nothing beats an authentic CTS replacement pot. Keep the old one. It may be salvageable. If you are lucky as I was, I found a tech to repair my mid-'70's Electro-Harmonix Big Muff that has a nylon-shaft pot that is no longer made. He looked up the value for the circuit, found a contemporary pot of the same quality, value, and taper, and transplanted the wafer from the new pot to the old pot to both retain authenticity and avoid having to find new knobs, which are all original on my stomp box, now @ 50 years old.