I can supply new damper rods and seals. These are specially made items as the original seals are no longer avaialble. Kit comprising of 2 rods and seal sets costs 143euros + postage.
Hagon? Doesn't really make sense replacing 40-year-old units with new 40-year-old items... applies to almost the same degree to Koni/Ikon.
If real suspension improvement is required, might be better looking into alternatives like Falcon, Maxton, YSS, Wilbers or even �hlins, depending on wallet capacity.
piet