Thanks for all the advice, guys! Much appreciated.
I guess the first step is for my garage to assess the damage properly - and reckon the biggest factor will be the labour cost to put it right, either way.
I am looking for some advice.... for four years have blissfully owned a 1988 1600tdi westfalia hi-top joker imported from Germany. Had just taken the really difficult decision to sell the van as we just don't get out in it enough - and I think the van overheard, as the timing belt went while driving...