Spax Shocks Adjusters can the be repaired? G453 model

[ginV8]

Its seems quite common but I've two working spax shocks but one adjuster has seized and consequently snapped when I went to adjust it and the other just turns but makes no adjustment? As such the damping in each cannot be matched and one is soft and one hard at present being sods law???

Does anyone know anyone who can replace the adjusters without my needing to buy new shocks?

Spax have not come up with any offers yet but the shocks have only done 9000 miles They were fitted in 2002 on a new dry weather open top car hence the low mileage.

Cheers in advance.