Its a hard one to find in good condition, your's looks in pretty good condition. I collect globes and gas stuff. My guess more to the $500.00 area. It was designed for the National A38 computer pump. This is mine.
Original globes can be pricey. There are repros but not to many originals in good condition. I couldn't find the kind of pumps I wanted a number of years ago and made two like I wanted. I needed something high because of the height of the building. I still have the molds for the tops I made out of fiber glass. The faces are 24 hour clocks. G.M.