The comic book Radar is sleeping with is Avengers #72 (January 1970); moments later, without Radar having moved, it is issue #60 (January 1969).
Camp announcements includes mention of baseball legend Ralph Kiner had hit his 47th home run which took place in September 1950. However, Col Henry Blake was killed off on the last show of the previous season, which according to the engraving that Radar O'Riley etched onto a bullet, took place in 1952. In the subsequent seasons of the Korean War, Kiner never topped 47 home runs.
While explaining the rules of draw poker, Klinger tells Major Burns that you draw, keep your best five and discard the garbage. In fact, you discard your bad cards first then draw.
Radar breaks a rule of draw poker by discarding 4 cards. Under standard rules, three is the maximum number that may be discarded. Also, he asks if it is Jacks or better, indicating that he has at least a pair ( less than Jacks). It's unlikely that he would discard 4 cards with any pair.
When Frank is talking to Margaret on the phone, Radar is sleeping. Radar is holding a comic book titled The Avengers. The Avengers comics didn't start until 1963.
The comic book that Radar is seen sleeping with in the opening scene is Marvel Comics' The Avengers, the first issue of which wasn't released until 1963, ten years after the Korean War ended. The specific issues seen are six and seven years later than that, but also five or six years prior to the filming of the episode.
When B.J. and Hawkeye are getting in the jeep to go get Frank: B.J. shows a package of Fig Newtons he was going to bring. The cookies are packaged in a manner not available in 1950-53.
The comic books that Radar is sleeping with, Avengers vol. 1, issues #60 and #72, are cover dated January 1969 and January 1970, respectively. Almost 16 and 17 years after the war ended.
When Radar discovers that Frank is missing and asks Hawkeye and BJ if they've seen Frank, they ask Radar if he's checked Margaret's tent. He replies that he has, and that there is a big padlock on the door. However, when Margaret returns and Frank escorts her to her tent, she just pulls the door open and walks right in.