I would just go to Home Depot and buy the Wayne water bug. I bought one for the same problem. Can move 1200g per/hr. This isn't a permanent fix but works.
I would recommend the Rotopax 2 gallon gasoline pack they can easily put on the roof rack and strapped down. They also look cool. These are used for off roading hooked to jeeps or land rovers so i would say they are durable.
http://rotopax.com/3-Gallon-Packs/