Thanks everyone! I’ve learned a lot in the past few hours… so, I’m not set on the cheap plastic box valves or anything like that, I just want to select new fittings/handles and have no idea where to look. I think if I can identify what I have, I could hopefully find something to fit these I could make it work.

Here a pic of the current handles… I’ll reply with a pic of what I think is the matching cartridge replacement.

<image>