When I bought some new hinges they had paper 14-thou gaskets but I used a piece of bicycle inner tube for it instead. Probably worth having something under the washer that goes between bootlid and nut, as well. I added this to try and keep down the amount of water that was creeping down the inside of the lid to rot out the bottom of the skin where they usually go.
Edit. Doh, forgot to hit send at lunchtime and got beaten to it.