My Vagabond, slightly smaller than your boat, has the SAME style rudder construction.
If the metal parts are all good... order mahogany and make the wood parts.
Note: Might ask the local High School if they have a wood shop class and you can get a kid to glue it up then run it through the planer.
It should count for one of their projects for a first semester wood shop student.
Then you don't need to buy expensive tools and the hardest part is done.
50-50 on the school cooperating if they have the wood shop. Worst they can say is no.
Appx $50 worth of mahogany should do it.
Home Depot, special order, but they can get it.
Dowel jig and dowels for piecing it together straight
Epoxy to edge glue the pieces to make up the width
You can use rope and sticks for clamping, but bar clamps are better and faster to get it clamped up.
Cut to the correct outline and hopefully enough of the old rudder is there to pattern the hole for pivot.
The hole for pivot and radius of the portion that rotates inside the side plates (there's probably a special name for the parts... I don't know it) is VERY important to have right to prevent binding.
Just rounding off the edges is adequate. or you can try to shape it to the OEM rudder's "thin airfoil" streamline cross section... (too much work for minimal reduced drag if not racing in my opinion)
1 part Tung Oil, 2 parts Mineral Spirits, 1 Part Spar Varnish. Coat the wood until it won't soak up the mixture any more and it pools on the surface. Wipe off the excess and then give it 2 coats of full strength of Spar Varnish. Then let it dry for 3 days and Paint it with 2-3 coats of Oil Based paint.
TAKE THE WOOD RUDDER HOME and hang it in the garage where it can dry when the boat is not being sailed. (and dagger-board if its wood)
The wood rudder can last more than 40 years with minimal care if you just store it where it is dry when not sailing.