Spurred by a conversation on FB, I remembered I had looked at this before and even bought the supplies to make one. Riff and Magenta both wear a single, spiked gold anklet on their left ankle during the take-over scene. It's not very easy to see in the film (maybe easier on the BluRay), but there is a great shot in the Mick Rock book (p. 257, though the photo
is reversed).
They are probably about 3" wide, and pretty snug fitting. There are 3 rows of metal spikes (1/2" or longer?) in a staggered array. The leather base (or whatever) is edge-stitched
You could use vinyl, but you'll probably want to back it with something more substantial to support the weight of the spikes.
