I see you are in Thunder Bay. I am in Toronto.
If you can't find a Beretta pad to fit maybe contact Stelios Chrysochou in Georgina?
Stelios installed a Pachmayr pad on a Beretta 691 and adjusted the LOP and Pitch.
And also installed a Silvers pad on a B. Rizzini BR550.
Like Brittany Man says above "plugged the holes for the Beretta pad with pieces of dowel epoxied in place, drilled new holes for the appropriate size Pachmayr pad & fitted it in the conventional manner."
Great work, fair price and a congenial fellow.
I know not close to Thunder Bay, but maybe can ship?
Stelios