need help identifying a shower valve

[Rick1803]

My son just bought a house in RI. Water drips from the bathtub fill spout. I think the shower valve must be leaking. Maybe it needs a new cartridge.

Can anyone identify the make and model of the valve in the attached two photos? I cant find any name on it, only the letters "SA" as shown in one of the photos.

 

[Mr_David]

Take off the trim and take another picture. Often the only way to identify is to pull the cartridge. Sometimes you can tell by removing the trim