I've seen them for sale at the Arcata farmers market, but that doesn't mean much. As you probably know nor cal can be pretty diverse in growing regions. I have the plant it and see if it works mentality, so you can guess what I would do. I think you have a pretty good chance if you're on the coast (the weather is pretty mild in the Arcata-Trinidad area), but once you get to the inland heat you may experience more problems. Anyway, I've transplanted a number of volunteer japaneese maples I find under established tress with little difficulty. Perhaps you could get some seed or cheap to free sprouts to try with. I see a lot of people on here worried about doing things the right way with permaculture but that seems to take some of the fun and experimentation out of it. I'd say if you can do it cheap why not try. -Just my 2 cents
On a side note apparently the big leaf maple (Acer macrophyllum) and Acer grandidentatum have been used for syrup, and Acer grandidentatum would be a better bet for inland locations.
here's a page on tapping big leaf maples:
http://arcadianabe.blogspot.com/2013/02/bigleaf-maple-syrup.html