That looks like a can-back top. I don't think they're in business anymore, but there are more pics online.
https://www.google.com/search?q=can-back&client=safari&hl=en&source=lnms&tbm=isch&sa=X&ei=TrlIUoDNOvDs2AWz7IG4BQ&ved=0CAkQ_AUoAA&biw=1024&bih=671&dpr=1