Two of the JSAers who hadn't been revived before the re-introduction of the JSA in Flash #137 (and thus didn't have Silver Age counterparts) were Dr. Fate and Hourman. Their Golden age history was notated here, but....they had a little early Silver Age spotlight of their own in two issues of Showcase!
The First Showcase
Psycho Pirate shows up again, facing the Spectre in Spectre #5 (July-August, 1968), and the JSA as a whole in All-Star Comics #66-68 (1977), and returning as Hourman's representative foe in the Secret Society of Super-Villians in Justice League of America #195-197 (1981) (continuing into All-Star Squadron #26 and Annual #2 of 1983), before working for the Anti-Monitor during the Crisis on Infinite Earths...and later battling the heirs to the JSA, Infinity Inc. (including Hourman's son, the second Hourman - Rick Tyler). Wendi Harris (the original Hourman's actress fiancee) was also a part of this issue.
No reason was given why the magic-based Dr. Fate picked the scientific Hourman...
...but this piece of retroactive continuity (telling a story set in the past to explain later events) seemed this formed a friendship between the two that lasted over decades...
Gathering of Foes
All this just goes to show how interrelated comic characters can get over time....it's like magic!
Just for completeness sake, here's the cover's of the premiere of the Earth-2 members of the Monster Society of Evil (though they aren't on the original covers...).
Nyola and Oom from All-Star Comics #2 and #3. Nyola created by Gardner Fox and Sheldon Moldoff; Oom created by Jerry Siegel and Bernard Baily
Ramulus (originally known as Nightshade, but DC was getting Nightshade, a character from Charlton Comics, and his original tale of World's Finest Comics #6 was reprinted in Wanted #9), and was created by Jack Kirby
Mr. Who (his first tale of More Fun Comics #73 was reprinted in Wanted #8, and all his tales vs. Dr. Fate are in the Golden Age Dr. Fate Archives) and was created by Gardner Fox and Howard Sherman; Mister Who's Solution Z allowed him to change size, become invisible and intangible and adapt to any danger.