If the vehicle can be driven (and has a current MOT, if required) then any decent vehicle logistics company should quote you TWO figures. One would be to use a low loader. The other would be for one of their 'trade platers' to drive it for you. (Trade platers have 'all vehicle' insurance and their plates carry their own tax disks, so you'd face no problems or extra costs relating to those issues).
However I've given lifts to a few drivers from Automotive Logistics (who are based in West Yorkshire) who gave me the impression that the firm was well-run, so they might also be worth a try:
http://www.automotivelogistics.com/