it's from Sunset Marketing, dated 1971.
It's got a catalog number and tagline. However, these would only show if the poster were rolled up with the image outward, which might be rough on the printing!
You can try to decipher the signature, or you can read the nitty-gritty from the Center for the Study of Political Graphics. As of right now you can buy one "near mint" for $139.95.
All I can say is, thank God we live in a country where such rampant free speech and dissent are allowed -- whether you agree with it or not. And whether you like or dislike whichever "superhero" or "supervillain" -- your choice -- may be leading the dance at this moment.
See you next Monday!
