VINTAGE 1980'S Keith Herring Free South Africa T-Shirt

Love worn Keith Herring "Free South Africa" shirt purchased in the 1980's. We think this is a size large, but are including the following measurements, as well: 22" wide, 25 3/4" long (from crew neck on back of shirt down to the hem) and sleeve openings of 7". In all transparency, there are slight yellow stains under the armpits, but they are not super noticeably. Also, there is one gray fleck close to the hemline on the front of the shirt (please see photo). This vintage Keith Herring design is selling for between $220 and $500 dollars on Ebay. Thank you for looking!