The mustachioed cowboy on the "now playing" posters and (to a lesser degree) the surprise lines coming from the fellow on top of the ladder's head are dead giveaways for Schwab, who per Who's Who also wrote his own gag cartoons such as this one (art spotting by Henry Andrews). Overstreet apparently also credits Schwab.
Signed in both the first and the final panel. The indicia for this issue is at the bottom of the first page of this story, which is the first interior page of the issue. The box at the end of the last page (blanked out in the Marvel Comics version) reads "CONTINUED NEXT WEEK".
As per scan at http://digitalcomicmuseum.com/preview/index.php?did=16991&page=52
Filchock wrote most of his own scripts, and early on most Funnies, Inc. staffers did their own lettering.
Also signed "G. Peter" in the last panel.
Signed with the artist's full name (although I cannot make out his middle name) on the final panel.
The seventh page was not reprinted directly, although the first six panels of the story in Marvel Mystery Comics #3 relate roughly the same events.