I’m looking for a water container that may or may not exist. What I would like is a flat-sided or soft-sided container that will fit in the pocket of my hunting coat. The pocket measures 6 1/2″ wide X 7 3/4″ tall X 2″ deep. I’d like to be able to carry as much water as possible, but don’t want to overload one side of my coat to the point where it’s uncomfortable.

Any ideas are appreciated.