In 1975 a group of Caltech students published Warlock, one of the first supplements for OD&D.

In 1975 a group of Caltech students published Warlock, one of the first supplements for OD&D. Holmes used this system for his personal OD&D games prior to editing the Basic Set. He was a fan of the Warlock spell point system and mentioned in Dragon #52 that he tried to get Gary to include a spell point system in the Basic Set. I've written up a summary of these rules if you are interested in trying them out, either in your OD&D game (particularly now the pdfs are publicly available) or in your OSR game.
http://zenopusarchives.blogspot.com/2016/02/the-warlock-od-spell-point-system.html