I'd get a quote from the dealership, then relay it to the guy that hit you. I would then do what Kash recommended and have the OE bumper removed and resprayed. I had the exact same thing happen to me except it cracked the rear bumper support/stay which needed to be replaced. Make sure the place inspecting your car checks for damage to the support/stay as well, they missed it the first time around on mine (dealt with insurance as it was a hit and run - and they found the guy via surveillance camera footage, so I was covered). It could put a nice chunk of change in your pocket for maintenance or mods.
"! First rule of Italian driving, that which is in your mirror is not important !"