rezeen, I bought those bags when you were pulling girl's pigtails in school but the big green one is from LL Bean. I'd imagine a wilderness outdoor shop would handle them or try to google them online. The big one holds all of my clothing and sleeping gear and the small one food stuffs and other incidentals. The ammo box holds my keys, wallet, medicine, knife, tools, etc.
One thing I'd recommend is a pair of knee high rubber boots or maybe a pair of waders to have in the boat in case you can't get all the way to shore (it happens).