I've found two different part numbers, possibly depending on model. One seems to be common with Fiat Punto, Panda, 500 etc and the other one is Panda only.
Probably worth enquiring at your local Fiat dealership with your reg/VIN number to ensure you get the right one.
The part numbers I found were 77365412 (L) / 77365413 (R) and 77366052 (L) / 77366053 (R)