What is the value of a Remington umc pump gun circa 1903?

A UMC CAN'T be circa 1903, it didn't become Remington UMC until 1912. I believe by the time UMC took over the model was on the receiver, it's probably a model 12 or possibly a later 121 if it's not quite as old. The value is GREATLY dependent on the condition, condition, and the condition, and of course which model and variation.