Indy, unless you're a marathon runner then you don't need to have a large amount of stamina. What most people need to work on (athletes more than any) is strength-endurance. This is acheived by cutting your rest time down, not by doing a billion reps.
Besides, why would you want endurance in just the arms and not the rest of the body? Personally, I think you should train the arms as you would the rest of your body.