Do you have any evidence that it was recorded commercially before you knew it?

Oh, that's a good one!

Back in those days, it hadn't been all that long since recordings had progressed from Edison wax cylinders to 78 RPM records.

Well, not really... but I don't think 45 RPM records were out yet, circa 1950. Back in those dark ages, making a commercial recording was not the semi-casual process that it is today, and only mainstream audio was likely to be produced.

tanstaafl.