Check with " oldengine.org ". This is a club out of Sandwich IL. Sandwich Illinois was an early manufacturing center for small motors. These guys have an excellent show at the fairgrounds by the way.
Highlander, I have one a little bit larger that was made to use on a free floating axle bearing spring loaded retaining nut (86, 89, 97 ford truck dana axle). The socket that you show looks very similar.
Irnsrgn, the stone lifting device you describe is called a "lifting lewis" .
(I'm a stone / brick mason by trade. However I have never used this device. I like to lift heavy stone slabs with nylon slings.)