These are nothing special, they come in several sizes and.can be found at any decent fabric store. Unfortunately, there are fewer and fewer of these every year as home sewing becomes less popular, but stores that sell upholstery fabric also carry them. A search for jeans snaps or even pajama snaps might work. The holdback straps on my sliding doors are these snaps. 2012 Eddie Bauer so it isn't vintage. The female side is 2 pieces that mate when punched thru fabric or plastic. The male side is affixed to the wall via a small phillips screw going thru the center of the snap.
Today is a gift, that's why they call it the present.