Silent Night, Bloody Night is a 1974 horror film starring Patrick O'Neal, Mary Woronov (Babylon 5) and John Carradine. Candy Darling is also here. This one was worth watching, and I'd be happy to watch it again with anyone else who might want to see it.
Internet Archive has it, as does youtube:
The Spinning Image doesn't give it a positive review but does say, "there's something about that mood that stays with you like a Christmas Eve ghost story". AMCtv has some information.