I found this answer from ebay's Reviews and Guides section by the username of rlmsport: THE FIRST ISSUE The most famous issue of SI is the August 16, 1954 edition featuring popular Milwaukee Braves' slugger Eddie Mathews on the front. It's the first regular edition and carries a value today of approximately $150-200 in excellent condition. To entice fans, SI's editors included a three-page center foldout of 1954 Topps Baseball cards. The 'cards' were actually printed on the same paper stock as the magazine, and included Jackie Robinson, Willie Mays, Ted Williams and other superstars. Collectors purchasing issue #1 should be certain this foldout section is intact. The inaugural issue was preserved by many who even then saw it as a collectible item. The folks in charge also had the foresight to save dozens of boxes of the magazine in storage, untouched since the day they were printed. SI delved into that archive in later years, releasing some of those pristine issues. Were it not for it's fairly widespread availability, the issue would likely carry a higher price tag. Still, it holds an important place in the minds of collectors, historians and sports fans in general. The second issue, dated August 23, also included a card foldout of New York Yankees and is actually more difficult to find and more expensive today. In '55, SI also offered the card insert issues that carry a similar premium.
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