I really don't understand what you intended to do about flipping the gear. If your distributor was 180 out all you needed to do was lower the pump clear of the cam drive gear and rotate the pump drive shaft with a screw driver to where you wanted it.
At any rate you best bet is always to choose a new oil pump. It's the heart of your engine. But if the pump really has very little time on it then a new driven gear would wor.