These are mentioned in the SCSW as "at least" 500 made, shipped to Germany without barrels, fitted with the part there and sold into the Italian commercial market, and 400% standard value of a 39-2.
Aside from the barrel, the magazine may or may not be different, as the rear of a 7.65 and 9 mm case are the same size (the bottleneck makes the .30 round smaller than the 9 mm at the tip).
A letter of authenticity would be highly recommended.
http://www.swhistoricalfoundation.com/swhf_letter.pdf