They are a present from my better half. A very nice gentleman came to visit me on repeated occasions to take measurements and make checks. It was more or less like being at Savile Row tailor for a bespoke suit. At the end, I was presented with a box; and have since never dared to ask about them, just being happy with the loupes and the glasses that are like any other ones.
Oddly, one can find adverts for these kind of glasses with loupes in the New Yorker – and of course on line.
Doing woodworking after corneal transplants: well, I stand in awe.