I am not exactly miserly, but I hate when I am expected to pay a lot of money for things that are not worth it. For example my used Mamiya RB67 came without a strap, and even it is is mounted to a tripod most of time a strap would be nice to have. But the ones you can get on ebay are too expensive IMHO — around 40 €.
So I had a closer look at the fittings on the camera and decided to tinker a lug myself. I used a 25mm mounting angle. It already had two holes. I drilled one a littler larger for the carabiner and filed the other to the shape of a keyhole, the smaller part with the diameter of the inner fitting. I made it a tad smaller, so that it sits tight on the fitting and doesn’t slide up and down — which could end dramatic. Then I bent the upper part 90° upward and ground the corners — finished.
Because I don’t want the carabiner scratch on the edge of the camera, I slaughtered a small key-pocket made of leather and cut two flaps as spacers. Perfect 
ps. Might work with other cameras with a similar fitting as well!