Part 1 booklet front
Goudey didn't work hard to create 1938's version of their baseball booklets. They just split 1937's 1/4"-thick version into two 1/8" halves and added player pictures to the front, hoping folks would buy the same quick shots a second time. They proved popular enough at the time that you can find them on eBay in the 21st century, making the set "obscure" instead of "impossibly rare."
Part 2 booklet front
Joe DiMaggio represents this set's prime appeal for modern collectors, as the 1937 and 1938 booklets precede his better-known 1938 Goudey Heads Up "rookie" card. The full 13-player checklist also includes HOFers like Paul Waner, Bob Feller, and Luke Appling.
Booklet back (same for both parts)
Goudey's bio called Moses a left-hander, but its shadowy batter swings like a righty. Is this booklet animating the wrong guy, or did Wally switch sides to fool the photographer? (Without better information, I assume it's a printing mixup and actually shows someone else.)
Page from booklet interior
Value: High grade Joe DiMaggio booklets cost a few hundred dollars, but lesser-known players like Moses run $20-30 in low grade.
Fakes / reprints: It'd be difficult to reprint an entire flip book, though folks might try it with superstars like DiMaggio.