Thanks Pab. I'll take off a wheel at the weekend and have a look. I figured that these springs would need to be replaced in pairs.
A bit annoying it must be said - the car appears to be in a phase of its existance when it is haemorrhaging cash
The wife is threatening to get rid of it - which would be a great shame, as I can't imagine anything as capable or characterful to replace it with (short of a Landrover!)