Murphy's original Christmas pack "find" did not include any 52s. He offered 53 to 63. The 52s showed up later as did post 63s. Now you can find them up through the 70s and some mixed. For me it would be interesting to know who first created them and when, and if they were really ever sold at retail anywhere
They are obviously still be cranked out today but by the same person or group of persons ? A different person or group ? Or multiple people and groups.