Hi I'm back on track for the first time in ages...
After towing the van into town I finally took the sump off... two sheared bolts, lots of shattered shell, one big-end and... a small chunk of piston skirt!
So... to get her running I'll either need one new set piston/con-rod/big-end, or preferably a set of four, and depending on extra damage, maybe a new crankshaft and engine block.
Any suggestions chaps?