Whilst I was having my saildrive gaiter needlessly changed in France (15 years old and still perfect) I decided to drop the rudder and fit a new Jefa lower bearing.
Unfortunately the Parklev dropped the stern of my boat through a radius instead of vertically and it tore the seal that sits at the top of a rudder tube mounted to a grp tube in the transom.
My UK yard gave me the name of a UK supplier and £8.50 later it’s as good as new.
Hope someone finds this useful in the future.
9cm outside measurement, 6cm inside.