Great, thanks for the info PaulAll of these boats with need this repair eventually and there are several solutions ranging in effectiveness and cost. Free and "better than nothing" would be install sleeves made from plastic jugs. I think you would need to drop the rudder to wrap the sleeves around the stock...
The other end of the spectrum would be to replace the tube with a modern system which has two bearings, one at the top and one at the bottom. The best systems have "spherical" bearings which can follow along when the rudder is loaded and its shaft bends. Big project, more money...
I can wish for one of those great modern rudder tube bearing systems for our i28 but am more likely to invest in a new Genoa... My repair will follow the strategy shown in one of the West System project guides.
They show how their epoxy system with a Graphite additive can be injected into the existing tube where it flows around the stock to create a new bearing surface. I think their guide was "002-550 Fiberglass Boat Repair & Maintenance".
Although you might perform this job with the boat in slings, you have to prep the rudder first. The best & longest lasting repair would come from having time to polish the shaft first. Some yards around here will accommodate a boat in the slings overnight. The correct epoxy would be cured in six to eight hours and you could be back in the water the next morning.
Also, I believe one of the "Offshore" magazines (Cruiser or Navigator) recently had an article showing a worn rudder stock getting "sleeved" with a new bearing surface.
Paul Comte i28
Cold Milwaukee, WI