I "liked" your post so you'd be aware someone responded.
If this is where you're going with this query:
I've got some fragmented collected data on the mass 6.5 rebarreling done in Italy and serial numbers buried somewhere.
Source dates uncertain, but certainly "a long time ago."
Also, I have some data on the cartridge itself from Fred Datig's book.
If relevant, it wouldn't be that hard to dig it out.