Deve, I am not aware of any vendor selling an all stainless speaker grille. So, let us know if you find one. If you can't decide on an interior color, no one will fault you if you stay original. I really like the color I painted mine: Dupont C8306 (Ful-Thane single stage). I think slightly more metallic than original and gray/brown in appearance. Even my color sensitive interior decorator type wife loves it!
I am going to spray a color chip and send to Denny. Maybe he will send to you after he is done, or I will make two chips if you are interested in seeing it.