This is a Factory OE oil pump for all "late" Fiat 1.8L DOHC engines after engine #572366, as supplied in Fiat 124 and 131 cars.
This pump has an elongated slot for the 3rd bolt hole, specific to mid-1976 to 78 1.8l engines.
Look closely at the shape of the pump base to make sure you're getting the correct unit.
Fiat 124 All (Mid 1976-78) 1.8L
Fiat 131 All (Mid 1976-78) 1.8L
New and unused.