A new radiator, although expensive, is a wise investment for a model T. The old radiators have over time, had the fins separate from the core which causes poor cooling. Also some of the tubes can be plugged.
I am not fimilar with the camco water pump, but water pumps might help a little bit if you have a marginal radiator. Usually if you have a clean block and a good radiator, you do not need a water pump.
Everything I have been reading about the water pumps. Says that they end up causing more problems. I saw one on the auction site. And thought it could not hurt.
A water pump is vital for slinging coolant all over your engine compartment. For cooling your engine, if the radiator is good and the system is clean it's superfluous.