You can't purchase just the mesh. Have to buy the whole grill. But you could get aftermarket mesh from ablaze grills. They have a few different styles which you can get in chrome or black. That might work best for ya.
My JEEP 2012 Black WK2 Altitude - Tinted Tails - Tinted Windows - Exhaust Tip - Painted Calipers
My Wife's JEEP 2015 White WK2 Altitude - Tinted Tails - Tinted Windows - Gloss Black Tail Light Bezels - Gloss Black Wrapped Window Trim