Los Angeles legalized pinball in 1971. How do I know this?
Because me and my Brother played pinball at a Hollywood Head Shop the night that Nixon was re-elected, and we had been going there for about a year. There was also a pinball arcade that opened in Van Nuys, Ca shortly after the L.A. ban was lifted in '71.
But it was at a traditional outdoor patio shopping arcade. The proprietor had acquired every machine that he could get his hands on, new or ragged. It didn't matter. At the end of the outdoor walkway arcade was a small room with pinball against all four walls, and the majority of machines were out on the outdoor arcade walkway. And the novelty of playing pinball was so great that most of them were in use, no matter the condition or antiquation or the less-than-level outdoor walkway.
And Disneyland is in Los Angeles County. I don't know if The County had a ban against pinball, or if it was only The City of Los Angeles (a much smaller, different municipality, but still located within The County of Los Angeles), but Disneyland (located in the city of Anaheim; L.A. County) had a Bally machine converted to a Pirates of the Caribbean theme in 1967. It was found in the gift shop which was located just outside of the ride attraction's exit.
EDIT: I believe there was Disney money behind Bally. There was definitely Sinatra by the late 70's. He promoted their Vegas casino.