Bob Purse, who has his own blog--The Wonderful And The Obscure--is a frequent contributor to the WFMU blog and he's the one we can credit for uncovering this long lost gem. His own blog has been featuring song-poems for quite some time and the Vellez label was known to have issued song-poems, but that wasn't the only thing they released. "My Christmas Won't Be So Blue" (backed with "Jingle Bells") does not appear to be a song poem release. The Allison Sisters were daughters of a North Carolina Methodist minister, it appears, and they recorded and released a very few sides in the late 50s and early 60s. Their Christmas single bears a radio station notation of "12-12-61", indicating this was released in 1961.
If you're like me, you are constantly looking for something....well, to use Bob's blog title, Wonderful And Obscure. The Allison Sisters qualify on both counts. Go find, listen to, and download if you like it, "My Christmas Won't Be So Blue" and "Jingle Bells" at WFMU's Beware Of The Blog.