You just might enjoy watching an early Christmas episode titled "Merry Christmas for Sweeney", from the Stars Over Hollywood" NBC-TV series starring Bruce Cabot as a newspaper journalist who's down on his luck during the holiday season. It's over there on YouTube!
Naked City had just one Xmas episode, which was in season one, the half hour format. In the hour long format, there's a season four episode "Hold For Gloria Christmas", but it wasn't about the holiday, and it was the first episode of the season.
Route 66 has an episode titled "A Fury Slinging Flame" from S1 w/guest star Leslie Nielsen as a professor who leads a group into the Carlsbad Caverns in New Mexico where they are holed up there, believing the world is coming to an end due to a nuclear holocaust on 1/1/61. Tod and Buz along with...