bladeswitcher,
Does you Bernardelli have screw-in chokes? I have a San Georgio, which is an Italian 12 ga. hammergun, that was made in 1973, by Bernardelli, I have been told. It looks to be an exact match for your gun. It has thin wall chokes in it, and I have always assumed they were done by a previous owner, since they are Briley tubes.
Though I don't care for the idea of screw chokes in a hammergun, it is really a very versatile gun for clays and birds. BTW, it's in the shop right now having the left lock sear recut and hardened.
SRH