I am not in your area but when I was in need of parts for my Johnson k50 I came across a website called PicClick, it is a search engine to help you search through eBay (and if there is an amazon leak) faster, I have been pretty successful with it in my search for parts on there.
I did a quick search for a 35hp Evinrude from 1958 and one popped up.
Another place I use is American Outboard Motors, you can call them and if they have one, they can send it to you if you want it.