Well we are stumped again! Plumbing fixtures can tend to be regional, Especially some old stuff. Today, brands like PP, Moen, Delta, Am. Std. are quite national, but even then buliders and developers tend to have favorites, so you do find clusters. Many smaller brands are not found at all in certain areas.
Most of my experience here in So. Cal. is in neighborhoods which are 35 years old and under! It is not mixed. There are NO older houses. I have some familiarity with some older neighborhoods down in the beach area. These mostly date from ~1950~1960. In the '50s I see some A. Std. After that, it's all PP. There is the Barber tract, pre WWII. The places which have not been remodeled seem to be Wolverine brass. Only place I have ever seen it. Brands like Sayco, Central, Symmons, Powers, are virtually non-existent. A very few old Cranes.
So, I hope some pros from back east somewhere ( East being defined as East of I-15) can help you out here!