Tips for introducing a different stim to a 3yr old

I was wondering if anyone had any suggestions for replacing my son's stimming while playing video games. He is diagnosed on the spectrum and has a big obsession with AstroBot on the PS5 right now. When he is playing he tends to jump and bounce around to stim which I don't mind as much. What I really want to change is his habit of sucking spit repeatedly when he gets locked in. I was wondering if anyone had any tips for replacing this stim with something less spit related and less noisy. I don't know what else might be satisfying nor how to go about introducing it to him.

I am undiagnosed on the spectrum myself and I also stim a lot but I have no idea how to influence one in someone else.