Friction nut

We are looking for a supplier of a certain type of friction nut. I
have posted an image on the web. The address is:

http://www.viewport.info/graphic1.htm

This little guy seems to be pretty rare! Any help in locating this
finding would be greatly appreciated.'Thanks,

Tom Murray’

I have bought such an animal from Rio Grande, or it might have been
Stuller. It was sold as a pin safety. Its been a few years, so I dont
exactly remember. It is slid on to the pin stem after it goes thru
the cloth and before the clasp, so that if the pin clasp comes open ,
the pinstem won’t slide back out of the cloth. Ed-Kokomo