This is one of 4 or 5 sets purchased by Bob Hritz at this year's Pomona show in California.  These are unissued, and came in a small group of them (in addition to some other irrelevant insignia).  According to Hritz, he had been aware of them for decades but was unable to buy them.  However, he did retain the poloroid photograph (see attached) which he had saved.  Good things come to those who wait!  Worn by members of a music school in Munich, these are extremely rare. All sets were sold by Hritz, and I was lucky enough to purchase one set.