X-Cart Mods: Product Options Copier for X-Cart:

"Why waste time adding product options 1 at a time? Using Product Options Copier with x-cart you can copy product options from one product to another with the click of a button. This modification will add to your existing product options, or delete the existing options before copying the new ones. You can also copy exceptions, validation javascript, and for XCart 4.X users you can copy stock levels and languages."