Well, I've gone with the simplest solution...
I've replaced the door with one from a scrapyard, I found the exact same colour car on ebay for scrap, went and picked up the door today, and swapped it over this evening
It was a bit expensive (£160) - but I got the door, with electric window, speaker, etc - so it was simply a case of taking off the doorcard and swapping the doors over... (I'm really chuffed )
On the subject of the van... there was no damage whatsoever to their van. They didn't indicate. They were on double yellow lines on the wrong side of the road, and the road my wife was coming from has give way lines painted on the road. As far as my wife is concerned it was a parked car, and the next thing she knew, it drove into her... but how anyone would go about prooving this without photographs at the scene, or cctv is beyond me