Big Horn Arms of South Dakota Info?

I finally managed to obtain one of the little oddball Big Horn .22rf single-shot pistols. The gun is stamped 22 SHORT ONLY, and on opposite side BIG HORN ARMS - WTN - S.D..



I once read that there were only 1200 made in the late 1960s, but so far I've not been able to re-discover the source of that info. When searching the web the name comes up as a rifle maker in CO, not the 1960's company I'm looking for.

The stock is molded plastic and has a very nice grip feel as well as a well-defined sight picture with its large sights. Very light weight gun. The original box (in background) is shaped to the pistol and even includes a plastic carry handle. Unfortunately its papers were not still aboard.

Any info on this little gem would be gratefully accepted.

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