Rare R. J. Braverman folding revolver and Stinger Pen Gun

A rare R. J. Braverman folding revolver and Braverman Stinger Pen Gun. The pen gun is of the folding type. Qualifies as a normal pistol and not subject to NFA as an The Stinger is something of a collectors item. But not exceptionally rare. The revolver is very rare. Its a tool rome sample built for testing. It was never produced commercially. I believe only a handful were made. I know that at least 2 exist, as Ive seen one other besides this one sell on gun broker. My best guess is that less than