A few from the UK (almost all concerned mostly with supplying police cars):

http://www.elsaction.tv/ (this site is not that up to date, they have other vehicles. Their police cars always seem to have CFZ codes on the markings)

http://www.visionmotorservices.co.uk/ (Note they seem to share cars with ELS but operate in the Midlands and the North whereas ELS are in the South)

http://www.tellycars.com/

http://www.shootingstarsuniforms.com/