Just ordered 2 of these from brigade quartermaster:
2.5 gallon Stackable Water cans
SCEPTER GI RUNT™ MWC 2.5 GALLON / 10 LITER WATER CAN
The 2.5 gallon Runt is half the size of the 5 gallon standard canister, which makes it lighter for greater portability. This military specification high impact plastic can will keep vital water supplies fresh and potable. Excellent for home, camp, cabin and preparedness survival storage. Srew top closure with a wide mouth for fast water point filling. Pouring is done through a small capped opening with a venting cap for easy pouring. These store compactly and stack on top of each. Each has a uniform, single handle that, in the dark, prevents mistaking them for fuel canisters.