Re:
Many thanks for the information! I can see one for sale on the German auction for 460 euro but it looks in better condition and older than the one I now have.
Will investigate the 3 speed hub when I'm home later and see if I can find any serial numbers to try and age it.
Think I might clean it up, put some fresh tyres on, replace cables and bearings and just use it at a general run about unless anyone fancies taking it on.