This is a damned good idea Chris and I nearly went for it yesterday but I dont have the space. If I did I would buy a goodish one as a start point, spend a couple of years doing a slow restoration to get it mint, then wait for a gearbox to turn up, which I am sure they will eventually. In my experience it is best not to buy the first release of something as at that point they will be rare and expensive, but sooner or later the price will come down - mezzies being one of the best examples of this..
I live 2 miles away from David Brown's Huddersfield factory if anybody wants me to enquire about the £58k upgrade!