You boys are getting awfully brave here...
Take her shooting. Most girly girls get off on the power-trip they get when they pop off a few for the first time. She'll feel like she accomplished something.
If nothing else, you could always buy it "for her" (sort of like Homer buying a bowling ball for Marge that coincidentally had "Homer" engraved on it).
If money is not an issue, buy whatever you want. The saying "one is enough" seems like a desperate plea for some exposure. Get on it