[Dave]

You could try staining the new cloth with tea or coffee, it will give you a slight yellow/brown color. Just brew up a pot and soak the cloth for a few minutes, rinse and lay flat to dry. Be sure to test a small piece or two first to get an idea of how long you need to soak it to get the color you want, and to make sure it wont shrink. I've never done this with grille cloth but I've used this method for staining some other stuff, works great.
-Dave