Just wondering what this is called. As you can see in the pictures one of the stems broke so i need a new one and dont know what to ask for. Thanks

 

Should be a coolant bypass valve or heater control valve. Vacuum closes it when the temp slider switch for AC controls is in the cold position. When closed it prevents hot water from cycling through the heater coils. Early models didn't come with one. It could be replaced with a splice with some loss of efficiency for the AC. Part should be available at most of the chains.

 

You should still be able to pick them up from the local dealer or the local auto parts store.