Check out this passage from Poul Anderson’s book, _Three Hearts and Three Lions_.  
A signboard hung from the gallery above the door.  
Holger read the florid script: 
“Martinus Trimagestus Magister Magicae - Spells, Charms, Prophecies, Healing, Love Potions, Blessings, Curses, Everfull Purses, Special rates for parties.”  
3H&3L was published in 1961.  
https://en.m.wikipedia.org/wiki/Three_Hearts_and_Three_Lions  I am reading it because it was mentioned as a source for a lot of the tropes that ended up in D&D, but given how that wizard advertisement is almost the opposite of Harry’s, I wonder if the book had an impact on Jim’s writing as well.  
(If you have an active Audible membership, you can get _Three Hearts and Three Lions_ for free.  It’s a fun story, and the reader does a good job characterizing and separating the voices.  A few have accents so thick that you really need to pay attention to get what they’re saying, until you get to know them.)