Meridian Plumbing Supplies

CC1

Hope you can help....I have a 4-year old stall shower in a finished basement that I rarely use, with a shower faucet built by Meridian, a company's that's NO longer in business. I called a plumber because the shower was leaking. He recommended I replace the cylinder unit made of plastic that's attached to the hot/cold volume control lever. The cover plate has two holes above the hot/cold volume control lever for screws, which attach to an interior mount.

I found out that Meridian was out of business when I tried to replace the shower faucet unit at the home store where I originally purchased it.

I DON'T want to tear-up the stall or the plumbing in the wall to replace the entire shower faucet. I'd like, instead, to replace the plastic cartridge unit. The home store where I originally purchased the faucet set told me it would be impossible to find a comparable cartridge, but it seems to me, from looking at the cartridge unit, that it's probably a stock item that's used by multiple manufacturers. I haven't called the plumber back to give him the news about Meridian being out of business.

My question....Is there a large plumbing outlet supplier out there on in the www that may have Meridian parts, or can I count on the plumber to be able to just repalce the plastic cartridge attached to the current Meridian hot/cold volume lever?