Wanna Steam up a plastic gun? Or just make a more "Yar!-worthy" prop gun? Here is a couple common cheap plastic pirate-themed guns you can paint to look like wood and aged metal that could be the perfect piece-de-resistance for your costume.
your choice of metal Rub n' Buff (Rub n' Buff is a brand name for a wax with metallic powders and pigments used to gild household items. Or Steampunk guns. ;) In this tutorial, you will see examples of antique gold and pewter)