I list it. But no body has ever ordered one from me.
Most of the time, these are bought at home centers and installed by homeowners.
I did install one to see how it worked, that's when I noticed that the seal was leaking and the trip lever started going out.
I posted that information, and then I started getting emails from others with the same problems.
The best way to gather information sometimes, is to have a place to find it.