Here's a source for the specs of various Porsche CIS control pressure regulators (WURs):
WUR specs2
Here's another good source of info:
CIS Primer for the Porsche 911
As for identifying which WUR, the last three digits of the Bosch number is typically engraved on the top surface of the unit. For example, my '83 SC takes a Bosch 0-438-140-090 WUR, which has "090" engraved on it. I can see some number engraved on yours; you may need to disconnect some of the stuff at the top to determine which one it is.