I'm in the process of replacing the rudder on my H28.5. I ordered a replacement from Foss Rudders (google it). Since my boat is on the hard for bottom paint anyway, I arranged with the yard to drop the old rudder myself which took about 2 hours. I measured the old one to ensure the replacement will be an exact copy. Al @ Foss has been very helpful. This all costs less than half of that $3500 you were quoted. I'll bet there is a website for your 33 that can give you the details of unhooking your steering quadrant, then you reverse the order on the installation of the new one.