ЯR Headstamp

Hi everyone,
I was wondering who produced (produces) the ЯR headstamp. I can’t find any information about this headstamp online. It seems to mostly appear on wildcats and such. Any information about the company would be great. Here is a picture of a cartridge with the headstamp:
(Photo from cartridgecollector.net)

This headstamp combines the two initials of the last names
of Mssrs. Ed Reynolds, of the United States, and Will Reuter,
of the Republic of South Africa. They provide collectors with
samples of wildcat cartridges, properly headstamped, as well
as Replicas of very rare cartridges. The latter give the collector
a chance to have at least a representative specimen of the case

Do NOT mistake these for any kind of fake. That is the reason for
the headstamp and applying the caliber. Anyone involved in cartridges
enough to even know about some of the case types they make will take
the time, as did Maynard, to find out the meaning of the headstamp, and
then realized their is no attempt a deception.

I have a pretty good collection of their auto pistol types, and like them very
much. Perhaps not as good as having original specimens, but then the price
is appropriate to the time and effort to make these, generally 20.00 or under,
and not in the hundreds and thousands of dollars like some of the originals.
Whether one cares about replicas or not is, of course, a personal choice.

JohnMoss, thank you very much for the detailed explanation of the headstamp and company.