Three wagons seen on the A303

Driving back down the A303 today between Basingstoke and Andover, I overtook two articulated lorries that were carrying, between them, three railway box vans (bodies only - no wheels).

I didn't get a good look at all of them, but one of them appeared to be similar to LSWR vans with external diagonal cross bracing. The others were I would say steam era, short wheelbase vans but wouldn't say more than that. At leats one, and maybe both, of the others had planked (rather than plywood) sides. All three appeared somewhat dilapidated, as if they had been recovered from a field or similar.

Any ideas what they were, or where they might be heading? The fact that they were undergoing a (presumably) somewhat costly move suggests they have a future somewhere?

Tom