Thanks Mark. That's what I thought I'd do. I checked both the Dorman site (including Motormite) and Hillman. Neither has 5/16" band style clamps. Sizes are 3/8, 1/2, 9/16 and 5/8". No 5/16". Guess I'll have to try the 3/8" clamps and hope they have enough clamp range to seal the 5/16" hose. According to the Dorman catalog, they are only available in a tray assortment pack.
Chuck
EDIT: After looking at more info on these style clamps, it appears the clamp size refers to the OD of the hose. My 5/16" fuel hose is about 9/16" OD. So I think I need about 1/2" - 9/16" clamps. And need to find them in black color.