Those were special issued to ECNALUBMA, er um ah, I mean AMBULANCE drivers in the early late 1980's as a defensive armament against the new phenomenon of "ambulance chasers". I am sure a letter from Roy Jinks will confirm this.
It is a well-known fact that Smith & Wesson tried to replace the lazy amphersand with its cousin, the backwards amphersand. S&W management hoped to increase production with a less lazy character.
While it was more energetic, the backwards amphersand insisted on doing everything bass-ackwards and thus actually slowed production instead of speeding it up as had been hoped. It had to be replaced almost immediately by the modern amphersand we now know so well.
Actually, it is an overrun from a MOSSAD contract. Like most Middle East writing, it is SUPPOSED to be read from right to left, NOT left to right, as in the Western World.
Even rarer, it might be one of the Golda Meir Signature Models, with her likeness and signature engraved on the inside of the grips.