This has been an excellent discussion. The AI can carry 7-days of fresh water w/o problem (1 gal/day/person in hot weather). One thing that has not been mentioned when discussing landing in surf on an extended camping trip, is that your boat is going to loaded with 150-200 lbs of supplies/gear. Couple that with a 115# boat, and you are probably not going to be able to drag your boat out of any pounding surf. Any one intending to do such a trip should have significant experience before undertaking the real thing.
I sail: Biscayne Bay, Everglades to Cape Romano, Ft Desoto, Cedar Key
"Any intelligent fool can make things bigger and more complex ... It takes a touch of genius and a lot of courage to move in the opposite direction." A. Einstein