You are in a bit of a jam because marine repairs
and cheap, easy and quick are rarely used in the same sentence.
From the photos it is clear that you have a bigger problem then just delamination
as there are rust stains seeping out of the multiple cracks in your rudder. Many boat
builders used metal (SS, or whatever) to build a reinforcing frame in the rudder and then applied wood, fiberglass
or both over the metal framing to build the rudder so that it could withstand the forces it needed to handle. Once the metal (the last line of defense) begins to rust it is compromised you are left with having to rebuild
the rudder which is a rather important component that enables your navigation
You can still do it on the cheap but not without a bit of effort on your part. I would advise you to take the rudder off the boat
, take it apart and have a metal shop fabricate you a new internal support system and then laminate the heck out of it with epoxy and cloth or even wood cores if you are willing to risk it.
Having a rudder or not is something you should not take for granted given the state of yours. Yours will break at the worst possible moment.