Just because you don't know him doesn't make him a "mystery man."
He spent two years in the rotation of Fresno of the California League, and was in camp with the Giants in 1972. Topps also auctioned these images off on eBay.
Toru Hamaura Minor League Statistics & History | Baseball-Reference.com
Topps did not photograph Kingman with the Angels or Yankees. Other than colorized black-and-white or blurry images from video there are no known color photos of Kingman with the Yankees.