OK, so definately not the one featured in the article I saw.
The thing that would worry me here is the registration. Is the W-reg the Series III or the Range Rover? If it's not the Range Rover, you could well have trouble with the vehicles identity and registrartion.
I know the chap is a bit low on paperwork, but you will definately need the registration histories of the donor vehicles. I've seen a number of restored or hybrid vehicles that claim to have an old registration but turn out to be new vehicles without claim to that identity.
Personally, I think for that money you could get a tidy 90/110 or Defender which might be a more sensible buy. If you are dead set on a Tdi, then consider a Discovery. You could easily get a L-reg or newer Disco for that money - giving you the engine and wheelbase you desire.
I'm with the advice you got above. If you have your heart set on this one, give it a month, then go round with a couple of grand cash and see.
Otherwise, keep your eyes open for a vehicle that is less likely to bite you in the rear. They are out there - you need a bit of patience and a touch of luck ...
... and consider a Disco!
Cheers
Blippie