Please google "gun parts", you will get a list of the usual suspects and more.
I would start with Numrich, Brownells and CDNN, and call as they cannot possibly have everything listed on line; then kindly ask them to check in person "if they got a chance".
They might also direct you to some other company.
Make sure to have the gun at hand or know its exact model.
I googled "armi tanfoglio 22 auto extractor" and it looks like the gun might be listed by some sellers under a distributor name, Excam or F.I.E, like here: www gun-parts com/excam/.
(please note everybody, this is not Numrich/gunpartscorp.com).
Tanfoglio.it in Italy might be able to help too.
And if you find them, buy at least two of each!