The Pop and Easy books are good. Popular Christmas Album by Mary Jean Zarick is fun and easy. If you tune in E flat, you’ll need to re-tune for Sleigh Ride. The International Christmas Book by Ortiz is a lot of fun. Several of them have religious texts but because they’re probably unfamiliar to your audience, they should be fine. RoJean Loucks has an Arrangement of White Christmas. I think Sylvia Woods has a four Christmas Songs books as well that has some of the fun popular tunes in it.