It would appear to be a Western Electric 1C2 model that has been converted to a 1D2 model. If you look inside, in front of the coin relay, there should be some yellow numbers and letters telling which model it is. You can get parts at payphone.com, or tullic.com. Payphone.com has pictures so you can see what the parts look like, but tullic.com has cheaper prices. The electronics board looks like a 32C, but I can't see who the manufacturer is. Inside the upper case, at the center of the bottom, there should be yellow numbers telling which dial unit it has and the date of manufacture.