Great, thanks for all the helpful information. This bike was completely Italian in build (a Marnati with all Campy and the rest Italian as well) so who knows. I was asking because it seems a lot easier to find an English threaded freewheel than an Italian one.
If it is Italian and I switch to English, will it be OK if I just stick to English threaded from here on out if I want to switch again? I don't intend on changing freewheels often, but may want to at some point.