Lost rare 1950s comic book with unique variant cover and 'Stanley Thompson' written inside, lost at a flea market in Portland.

I lost a rare 1950s comic book while visiting a flea market in Portland, Maine last weekend. It has a unique variant cover and was well-loved, with the name 'Stanley Thompson' written in pencil on the first page. I'm heartbroken, as it's been in my collection for years. If anyone finds it, please get in touch!