Original plans for old boat

[sailing1258]

I would like to obtain a copy of the original plans for the wooden-boat I am working on. I would gladly buy a copy of the original blue-prints if they are still available from any source. The boat is a 21' Sunray cabin-cruiser(wood) built in 1957. Has anybody ever heard of this particular cruiser? I can find nothing on the internet of any old boats of this make.