Well, when dad built the house 6 dog years ago he used elkay shower mixing valves.
After 5 c of years one developed a drip when it was turned off, so dad just put a ball valve on the shower head and didn't use it.
Now considering these are sweat soldered in, shower is tile I'll probably not match, a lot of work to cut a bigger access hole in tile to swap them out with current manufacture valve with Remodel trim kits,
I think I tracked down the cartridge that hoes in the valve bodies.
Granted it was by picture only, and figured that a gamble on it might work would be better than the $$$ and effort to replace valves. Yes the valve body may be worn, but worth a shot at trying it.
So i used some jedi google fu and ordered one. When it gets here, I'll swap it out. If it works ill order another for a spare if/when the other one has issues.
40 plus year service life I can't really grumble about.
Now the plumbers that were here for other things I couldn't do, well I think the hot into me a bit on labor..
So much for trying to stay local..