You can always call Benelli. Does it have it on the parts breakdown in your manual? The other thing you could do is take some drill bits and, using the shank end, see approximately what size the hole is. Then, see if your local hardware store had some brass rounds the same diameter and fashion one yourself. Should be a pretty easy fix.
"Pain or damage don't end the world. Or despair, or ____ing beatings. The world ends when you're dead. Until then, you got more punishment in store. Stand it like a man.........and give some back."