Thanks for your response. The mixer valve is a Moen. From the Moen web site, it most resembles model 2605, consistent with a builder's special (cheap) like other plumbing fixtures in the house. From the parts illustration (adobe page), the replacement cartridge parts number would be 1200 or 1225. Is it really chrome? It looks more like stainless steel gray to me. Is the cartridge easy to replace. How do you remove the adjustable temperature stop and stop tubes? Removing the escutcheon and knob was easy enough.
ps - could not get to you through e-mail, received delivery failure messages