"Rec Ball", Summer Camps, Other Options to keep playing in NorCal

My son is 15 1/2 and is a freshman is HS. He tried out for the freshman team back in Februry, but unfortunately didn't make the team. He took a couple of weeks off to think about things, then decided he was going to keep playing and tryout for JV next year. I got him on our local LL Senior Div. team and they play a short 4 or 5 week season, Mid May to Mid June. So a few questions. From what I know of the "travel ball" teams in our area all have full rosters by now for the summer. For those plugged into the SF Bay Area baseball scene better than I am, does that sound about right? Or are there some opportunities I'm missing. (Btw, in terms of location we're in the Fremont area in the East Bay) So I think the only option for getting him some playing time this summer would be some baseball camps. Maybe a couple of the week long college camps in June or July? Anyone have any specific recommendations for college (or other) summer camps? Are there any programs out of state I should look at? Any one have any "out of the box" ideas?? Any 15U teams in North Dakota needing a warm body or is there a "BAseball Island" out there somewhere that I've not heard about?? .. TIA for your comments and suggestions.