Link?

The one I bought in the early 80's, that clipped to the edge of a Bell Biker helmet, was really excellent. I don't remember the brand; perhaps CyclePro. It was just a piece of wire and a round lucite mirror. I stopped using it when I could no longer get a helmet that it fit. But after trying out all the mirrors then on the market (10-20 years ago) I gave up on the new junk I figured out a way to zip tie my old one to my helmet liner, and I continued to use it until the lucite mirror fell off and I never found it again. Since then I've been using a Take-A-Look mirror, which appears to be the best thing on the market now, but (though much more expensive) it's nowhere near as good as the cheap one I had in the 80's.

I'm going to see what they have at JoAnn Fabrics!