Can anyone give me some history on my vintage Zippo Beechcraft Baron lighter?

I cannot find a date stamp anywhere on the case or the inner portion of the lighter. My grandfather received it with the purchase of his 60's twin-prop Beechcraft. It is a slim lighter branded with "Zippo" on the bottom of the case in a sort of handwriting script. The plane painted on the case is white and yellow, with black wing tips and pinstripes. I'm interested in how common or rare this lighter may be, and what sort of value it may hold.|||You can go to Zippos Web site. They use to have a nice guide on how to look up lighters and there age. I used it several years ago.