Paul Reed (Capt. Block) and Sammy Smith (the ticket seller for "Little Miss Pioneer") were starring on Broadway in "How to Succeed in Business (Without Really Trying)" (one of the options for the boys to see) at the time of broadcast. Sammy went on to reprise his role in the 1967 movie.
Johnny Scout (the character) we never see as he really is (a woman) is the first television appearance of Janis Hansen, who'd go on to play Felix Ungar's (very) womanly wife, Gloria, on The Odd Couple (1970).