I Found a single reference to it in the book 45 RPM: The History, Heroes & villains of a Pop Music Revolution. The book refers to the release as a 45 and to Milton Cross as a source of the music. These may be both incorrect. My copy is clearly a shellac 78, but still sports all the packaging described. It may have been later released as a yellow vinyl 45. But the reference is still informative.
"One of the first 45 records with a full color, four picture sleeve was a recitation of "The Night Before Christmas" (47-0141) by Clement C. Moore, with Music by Milton Cross and the Victor Salon Orchestra. The record had not only a sleeve with an aerial shot of Santa Claus and his flying reindeer but also a fold over flap with another full-color illustration of angelic, caroling children. It was issued as part of RCA Victor's Youth series in 1949."So the real question was "Who is Milton Cross?" It turns out that he was the announcer for the Metropolitan Opera broadcasts on WABC-AM for 43 years. That's from their first program in 1931 until his death in 1975. He was also host of a classical program called "The Chamber Music Society of Lower Basin Street."
He was first hired by Tommy Cowan at WJZ-AM in 1921 while it was still based in Newark. It relocated to Manhattan as part of the NBC Blue Network. He did several children's programs including "coast to Coast on a bus", "Presenting A&G Pipsies" and "Children's Hour." With all that in context it begins to make sense that he be tapped to narrate that old Christmas recitation. RCA also had him read Little red Riding Hood and others. he also did some lesser known narrations of "the Great Foodini" for Caravan records. More here.
Late in his career he did a sunday night swing show and even hosted the Quiz program "Information please." George Ansbro wrote an autobiography in 1986 that tells as much about Milton as himself. It was reprinted with an introduction by Leonard Maltin in 1999. More here.