Rudder repair

I am working on a Flying Scot that I bought last Fall. The rudder is made of 2 pieces of wood with a thinner piece sandwihiched between them. My boat #436 is from the 60's. I don't know specific year yet. My question is what type of wood should I put in the middle? I think the outer pieces are Mahogany but I'm not 100% on that. I will try to include pictures but I have been having difficulty uploading them. 

FS5516's picture

Your boat number seems familiar to me. Where are you located? If you are near Connecticut, I can meet up with you to look at your rudder head.