I have one just like it, used as a drive plate for turning between centers. I don't own any bent dogs......
A family member once had a Cocker Spaniel that was that way. Or so her "dom" of a wire-haired terrier too-often tried to convince the poor creature.
You'd have to know Terriers and boredom enough to pounce up onto a living room sofa, snatch a corner pillow for partner, fling it onto the carpet, jump back down, "mount" it, and shag for dear life.
Just in case you thought Hollywood's human debris had the patent on weird.
As to driving plates?
Any OEM faceplate with Tee slots and a sliding pin with a resilient-padded "fork" (stock hardware-store clevis + cuts of "heater hose", braid-in) to suit the working radius of a whole tribe of the "grinder-style" straight-tailed dogs is actually smoother and more cooperatively
reversible as well as more adaptable to size. Most especially if working tapers, TS set-over.
An ignorant bolt, stack of warshers, 180 opposite is yer adjustable counter-mass, higher RPM's.
Gotta love the flexibility of legacy faceplates, after all?
Not the same as a Rzeppa CV joint drive, but close enough, far smaller, and dirt-cheap to DIY.