Thanks all, particularly Jim & Niven.
Well, transpires, buried in a stowage area, we have a brand new spacer and the other aluminium fitting (containing the worm and cogged wheel) for the VWC 1200. Basically => problem solved
. Should go and buy a lottery ticket!
Have painted the inside of the spacer with a two pack epoxy
... did the same with the old one - to protect the aluminium from direct exposure from the salt
Of course, the trick is how to prevent the salt water
coming down the shaft in the first place!!