Christening Decoration Ideas

You might look in local dollar stores. Some carry party favors and, in my home town, I've seen some for christening/baptism type parties. White candles, white crepe paper, white artificial flowers, and white "pew" bows tacked to the fronts of the tables are some things that come to my mind. They also have special confetti for different types of parties. If you have a local craft store, try in there. Ask the ladies there for suggestions. They're usually very helpful and come up with lots of ideas.
I hope this helps.

I am no expert and am not up on what is politcally correct anymore but judging from your use of "christening/baptism" I had several things pop into my mind. What about white candles, doves, angels, crosses or crucifixes? Maybe even little lambs, kinda a double meaning there. I know that angels are still "in" and you might find charms, christmas ornaments, etc for favors that wouldn't be too expensive.