There's a similar problem with some old Vivitar lenses. Here's the version I made for an old 20 mm. Vivitar, using copper. Because it's folded over, it need not be very stiff. In this case, as you see, there's only the one screw to hold it all, and at the time I did this the lens was being shared between an F and an F3, so the claw stayed on.
e.t.a. Since the AI tab is not at the same aperture on all lenses, I wonder if you could mass produce a tab with slotted screw holes, which one could then adjust to different lenses. I don't know whether it would be possible to make tight enough, but perhaps with the claw over the top it would, or perhaps once positioned right you could use a little dab of adhesive to keep it from shifting.
