Tom:
I suggest you get ahold of one salvage yards in the gulf coast. There were enough of the Hunters from that era that you should be able to find the base. They were an extrusion. You can probably go to a machine shop and have one made, but I am sure that it will not be cheap. I think that the design was changed on the later model and they used a more traditional type stanchion with a bolt thru the bottom (goes thru the toe rail) and a support leg that screws into the deck.
I think I have some photos of these from Steve Penny's H'31. I will see if I can find them.