Rare Still Kesey Poster signed by ken Kesey

Still Kesey Box Poster signed by ken Kesey. This poster was for a show by Ken Kesey to promote his Demon Box book. When I bought this from Ken, he said there was only a handful of these posters in existence. The image is a self portrait by Ken. Signed in gold paint the poster is in mint condition and measures 24" x 15". Possibly the only one of these posters signed by him.