Life Straw $20 They might be 25 locally.
It filters 264 gallons.
Blue barrel? Free. Your local body shop or carwash will tell you to fill your truck up with them. You have to clean them.
If you fill it laying down on it's side, you can just roll it a little to fill a bucket.
PrepareNOW Outfitters LifeStraw Personal Water Filtration