Sorry to hear about your incident, but at least you're ok and all that. These things seem to happen. I heard and felt a massive bang under my Passat on Tuesday night, going round a steep downhill right hand bend. I hadn't hit anything, but my nearside front coil spring just snapped. I had to drive on carefully for about 20 miles to get home, but it was an absolute pig. I'm sure the car had taken a pounding due to the state of the roads which contributed to it, but I doubt I'd get anywhere with a claim.
As for your car, and upgrading to .:R bits, the .:R bumper is quite different. It also has DRLs built into it and no fog light apertures. If all you have damaged is the grilles, them they will be easy to replace. You could probably get away with a smart repair to the damaged paintwork as it is so low down on the car.