I have sold my disco, so now have a bit of money to spend, unfortunately most of its going towards a shiny round thing with a sparkly bit on top, but I also have a bonus coming shortly from work :D
In the mean time I have found this:
Guide to Defender Door Repair | Repair My Landrover
via this post on the forum:
http://www.aulro.com/afvb/90-110-130...ust-doors.html
Also now found a source for the seal channel I was chasing:
051 Range Rover Classic Door Gasket Holder
Feeling much more confident in attacking the problem properly now. Doesn't look hard at all to do.

