Thanks all for all the suggestions.
Looks like I'm narrowing it down to a Marc Vito, ply-lined with a double bed and space for the bike (like the carpet-tiles suggestion Ant), or a boring car + tow bar + folding trailer that can go in my tiny front garden. Heart says van, head says car.
Special thanks to the offers from Ruthie & TP for use of their wagons/trailers. I'll almost certainly take either of you, or both of you, up on that offer in the near future!
In the few weeks while I sell the car I'll be keeping an eye on fleabay in case any more of those tasty race-vans come up.....
Cheers,
ali