If you want to rivet the handle together, any1/16"(1.75mm) rust proof metal will work. Solid brass escutcheon pins are great because they are already headed on one end. It is easy to find fine silver wire which is very nice to work with and not terribly expensive. Just be sure to get some 0 size washers. The washers are important because they stop the expansion of the river shaft thereby preventing the splitting of your scale material. If you want to use machine screws, in addition to the online sources, you should be able to find suitable miniiature hardware at a hobby shop that specializes in radio control trucks and/ or scale model railroad.