It’s a Commer Q2 tractor – Art Toys do a 1/76th scale model with a trailer, however Blitzkrieg Models, a distributor of rare foreign kits in the UK, have the tractor on it’s own, made by Art Toys for them – it would be perfect for putting on the Queen Mary Trailer. Blitzkrieg models web address is http://www.britland.co.uk/blitzkriegmodels/ from what i’ve seen the model of the Q2 is very nice, the Bedford OX tractor you get with the RAF recovery set is too small for 1/76th anyway so it’s worth replacing.