Kenneth, go to www.explorer-group.co.uk select 'Further Information' then 'product archives' then '1997' then 'Connoiseur'.
The van was fitted with 175R 13C 6 ply tyres. I suspect that the speed / load rating is 94N so try to get 8 ply rather than 6 {i.e. 175R13C - 94N 8 ply}. Do you know the recommended tyre pressure, i suspect approx. 50 psi.
The wheels will be 4 bolt fixing {I think 5 stud came in with 14 inch wheels around 2001}. The wheel itself will need to be 5J {5inch width} for this width tyre.
It may help you to read the thread 'Hankook' tyres as this size and type are becoming hard to find and only manufactured by a very small number of manufacturers.