1999 Pontiac Montana Water Pump

I just had the water pump change because the mechanic said it was leaking. In looking at the engine and what I think is the water pump, it has not been changed. It has the 2" hose coming from the bottom of the radiator attached and is driven by the main accesory drive belt. If they put a new pump in is it possible that they didn't require changing the housing or did I get ripped off? It looks like they took the drive pully off from the marks on the attaching nuts.The pump cost $63 For total cost of $126.