The car in the video is this one http://gtapolicemods.com/downloads.php?do=file&id=9
Its an older model, but its the best one I can find with a code 3 2100. I know there was a newer AST version, but that one the red and blue colors are to faint. They almost look white.
Since I'm using my local PD skins, they have 2100s, so that's why I'm drawn to that particular light bar.
As far as damage modelling, by that you mean can it be damaged ? If so yes it can be as long as the lights are off.