Hi,
Call Todd at Dreamworks, 386-852-4793 after about 10:00am est and he will sell you just the tanks. They are Robart tank's and he will know the exact size for the Sprint. The price's run anywhere from $9.35 to about $13 and change. I believe he sells them for the same price as Robart does. Here is a direct link to his page that has the tanks.

http://www.dreamworksrc.com/catalog/...p?cPath=46_175

Doc...