How long is a piece of string?

Is it a matching chassis? If the chassis doesn't match the number on the plates then you only have a van.
Calculate the cost and time of restoring to the level you want and add that to the price. Also asses what parts will be required e.g. GTS stuff and a twist type fuel cap. Do you want the original motor? It's up to you.

Some people pay $2k for a 'needs work' Sandman, someone might pay $7k for the same Sandman - value is in the eye of the buyer, while beauty is in the eye of the owner!