What a sweet kitty! Can you post some more pictures? The angle on that one isn’t great for identification purposes.
I’d say he’s not a California Spangled, though. They’re not bred, I believe at all, anymore, being overshadowed by the Ocicat in the attempt to create a fully domestic wildcat lookalike. In fact, California Spangled Cats are not recognized by CFA or TICA, it’s just always been an extremely rare breed, with less than 60 cats ever having been registered with TICA (where it was a recognized breed up until 2000).
I looked at other pictures you've posted. I would describe your pretty kitty as a brown tabby domestic shorthair, broken mackerel tabby pattern (some stripes, some spots). This color and pattern is seen very often in the domestic cat. Most cats do not have specific breed ancestry.