Stoots,
Nearly 30 years ago, before 'scoped handguns had gained much credit, I put a similar--note that I said similar--mounting system on a Ruger Security-six handgun. I really don't remember the base manufacturer. Then a little Bushnell 'scope was mounted in place. There was not too much selection in brands of anything involving 'scopes on handguns--or at least that is my memory!! Anyhow, I was the "talk of the town" being able to hit 12 ounce beverage cans at 65 yards with this 357 Magnum when it was placed on a very good sandbag rest.
Now to the reason I am posting this. Eventually, the screw hole threads stripped on the on screw that held the base to the area of the handgun where the rear sight had been. It had to be removed to put the base in place. Luckily, a good 'smith in the area was able to drill and retap it so the original rear sight could be put back in place. This was only a 357 Magnum and recoil was not all that vicious. Be careful if you are putting this type of system on a handgun that might have much more recoil than my 357 Magnum. Maybe the Weaver system is much better than the one I had. Anyhow, good-luck with your venture...BCB