Mine is unlabeled also and the locking clamp wore out. I just ended up making one out of a socket head cap screw. O1 tool steel would probably have been a better choice, but so far this one has held up pretty well.
HJE, aka Epstein's an epic resource, not 5 miles from where I am. Impressive all around, going on 8 decades of supply to the trades. My Dad [99 now] was a customer, picking up for his Dad [my grandfather] when they opened.
PEC also a respectable family business. Son runs it now, his engineering school project is this, the much copied swiveling inverted "Y" round stock center finder. Son runs it correctly too; imagine that!