Mystery Collar Tips

These are little metal tips designed to clip onto the points of shirt collars. I do mean little; the long edge is about a half inch long. The one on the left is showing its back with the locking tab flipped open, and the tab is marked "int. pat. pend" - "Germany". The one on the right is showing its front, which is very plain, just a little bit of metal edge for the very tip of the collar. I got a couple of pair of these at a second-hand store, and would like to get more, but I don't know where to do so. I've never seen anything like them except for the much larger and fancier ones made for western shirts. Can anyone help me solve this mystery?

UPDATE: The mystery is mostly solved. These were sold by Avon as part of their Sawyers (mens gifts) line. donsimpson.deviantart.com/art/… Some remaining questions are:

(1) Did Avon have an exclusive on this German design, or did another company sell it elsewhere? (there is a German tradition of collar decorations that it may derive from)

(2) Where can I get more of them? (which is what I'm most concerned about)

UPDATE: Thank you, fellow deviants, for your help and suggestions in this long quest. I now have enough of these for my immediate needs, though I am still interested in learning about their history, and about anyone selling them.