$35 bucks for 1000L, and it does filter out viruses and parasites also. Lifestraw is not a bad option for individual use. They make a family version also that's good for 15000- 18000L.
Thanks Doc! That's really good to know. I figure a couple of these in the kit+some iodine boxes should cover things. I think Dad's got a 500l plastic water tank somewhere he's not using either so I might have to...seize it in the name of the Crown.