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These are fairly contemporary Airshow posters and they would currently sell for an average of $20 each on today's market. You would likely garner more, in this case, by having the collection of Air Show posters sold together as a collection that had been gathered over the years as opposed to individually. This is not the norm, but in this instance the collective value may be higher given the young age of the posters. I recommend contacting Chisholm-Larsson in NYC if you are considering selling. Here is a link to their site for you: https://www.chisholm-poster.com/
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