Another option is to swap them for non-metallic pulls. I had a bag which had a couple zipper pulls eaten up by baggage handling equipment, so I'd replace them with nylon cord pulls. I was able to buy a pack of 5 of them for a couple of bucks at a sporting goods store (Galyan's, I think).

The side benefit is that you can get them in a color to make your bag more visible, like the colored ribbon or luggae strap.