wow that sucks mate sorry to hear this!
I did something similar a year or so ago and for the touch up and respray it was about £150 if memory serves me so guessing around the same sort of price
Make sure you go to a decent place as the respray they did on mine didnt match the rest of the car (luckily, or not depending on your view, I had another clip later in the year and the other place I went to (in Bham) resprayed the rear bumper for free to match it up with the rest of the car

)