Nalgene offers a tubing "kit" to convert one of their bottles (with the straw type lid) to a water-on-the-go rig. It's little more than food grade tubing with a crimp but.....with a Nalgene bottle hanging off of a belt in some type of colorful insulated carrier, it won't look very "military". Plus, many water filters adapt to Nalgene bottles.

Just a thought.

Harley