Hi Simon
I will check my spares later today. I dont know if it will make a difference but is your rudder stock a type 1 or type 2 ? From your photo the pintle appears to be fairly corroded. Were the fastenings stainless steel? It should be possible to patch repair it by welding it up – that would keep you going for another season or two. I would look at having a new aluminium one made with an aluminium pin as well to reduce the amount of dissimilar metals below the waterline. See the attached PDF for recommended grades of aluminium for each purpose.
I will get back to you once I have checked my spare rudder.
Murray A87