Pretty standard looking rudder gudgeon on the hull... but the door hinge mounted to the rudder is just wrong. It probably functions to permit steering, but the entire set of parts that are supposed to be on the rudder are missing. There's no spring loaded kick-up system to prevent ripping the transom of the boat apart if your rudder hits something while you are sailing.
There are ways to make your own functional replacements if OEM are not able to be located. Basically 2 aluminum plates, some bolts a bungee and 2 straps, then a rod to act as the hinge pin.
A picture that shows the whole rudder you have will probably show that the rudder is a scrap of wood, not OEM and the tiller handle is probably just some convenient piece of wood (maybe a broom handle... I've seen it done before)
For steering the boat you can get away with anything that works... until you hit a log that is just "floating" below the water surface.
Just so you know, the Super Porpoise doesn't have the spring on the rudder like a Sunfish. It just has a big lead weight at the bottom of the rudder to keep it in the water. It's free to swing up if it hits something, the weight will pull it back down. This also presents a problem when you attach it to the boat before backing down the boat ramp to launch. It hangs pretty low, and it's not easy to get it up and keep it up out of harms way.
Gail, I can take a picture of my rudder and post it(maybe). The metal part is a substantial piece of bronze.
An excellent pic of the Porpoise' metal tiller "loop" that simultaneously carries the mainsheet (substituting for the traveller), and returns the tiller to the centerline. (For those who want this option).