A few thoughts:
1. If you're on vacation, maybe you can make do with (slower) overnight charging whereever you're staying. That's what destination chargers are for. Last spring I did a trip from the Bay Area to San Diego, we used Superchargers in transit with a destination charger at our hotel in San Diego. It was "only" a HPWC at 30A but that was perfectly sufficient for us. Superchargers are most useful when you need to charge quickly (like you're on a road trip and you need to charge right now to get to your next charging stop). Public chargers can be found on PlugShare.
2. There are a few Superchargers that, while not exactly in the South Bay, could be useful, such as Dublin, San Mateo, San Mateo Bridgepointe Center, or Gilroy, depending where one is traveling. These are visible to you on the in-car navigation, the Tesla Web site (
www.tesla.com/findus), and various trip planning Web sites and apps. Admittedly the Superchargers in the Bay Area are quite busy, and I pretty much never use them (nor do I need to). If I'm travelling outside the Bay Area, my first charging stop is usually well outside the Bay Area itself.
3. More Superchargers are under construction (doesn't help you now but for the future), such as Cupertino, Sunnyvale, and Fremont Hub.
supercharge.info has some unofficial pointers to ones that are known.
Bruce.