As with most things I have an inkling this particular gag is a pervertable, I was wondering if anyone recognizes it for its vanilla use so I might find a more common venue to buy them from.
You get a similar effect from taking apart the links to a pincher collar and use a rubber o-ring to attach to the outside of the links.
Basically turn the "pinching" part into a hook for the sides of the mouth. And then attach the rubber o-ring (you can get them at any plumbing supply place) and tieing them around the back of the head. It's kinda funny actually.