If they are the smaller diameter size (thats what I'm thinkin your talkin about). I had asked the owner of the Capri, which is in Caro MI when he came out to my dads deerhunting. He has alot of deer friends. Anyway he just said he ordered them from Italy. I know not much help.
I used to go to this one deli in Nevada City that carried an Italian pepperocini that was sooooooooo good. They quit carrying them some years ago and I have never been able to find any since. It seems the Greek pepperocini has a toe-hold on the market . I remember the Italian peppers to be a darker green and had almost a spinach kind of flavor to them which is probably why I liked them so much. Not very hot but damn tasty!
Dunno Glue,but I DO know the best ones I have had made on a commercial scale were the Progresso ones. Have not seen them in a few years tho. Dang..another brand I like can't bring it to mind..will ponder.