Complex sentence: In September 1965, Stanley became the primary LSD supplier to Ken Kesey and the Merry Pranksters; by this point Sandoz LSD was hard to come by and "Owsley Acid" had become the new standard.
Split into simpler sentences: In September 1965, Stanley became the primary LSD supplier to Ken Kesey and the Merry Pranksters. By this time, Sandoz LSD was hard to come by, and "Owsley Acid" had become the new standard.