I live in the same area as you, and I have encountered that issue several times with Summit and other companies with products that cannot be shipped to California. I have made several trips to Summit, and I had to also make several trips to paint suppliers in Nevada to get the products needed to paint my car. Ironically though, if you do a bit of searching, there are a lot of companies in the other 49 states who do not give a crap about California law. They will ship products here even without the state's blessing.
California governing is only going to get worse in this regard.. They don't like any cars that are not electric, and they despise gas burning collector/enthusiast cars almost as much as they hate people who own them.