The process used on that is called a PMT, a photomechanical transfer. I know that process was available and utilized in the mid 50's, and through the 60's and into the 70's seems reasonable. There are a few guys on here who have mastery of printing processes and can better tell you; I'm not among them, my knowledge falls short.
I think what Robert and David offered is correct. And early reprint seems likely to me.
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