Answered[ Edited ]
Here's a link to the $10 and under and the $25 and under items at Sephora-
In the under $10, I think a pretty nail polish would be appropriate. The Philosophy Parties for Hosting and Gingerbread duos are nice for $15. If she wears makeup, the Sephora Mini Shopping bag is an awesome value at $15. The Philosophy shower gels are also nice and come in a good variety of scents.
Actually, there are just so many choices in the 2 links, hope you can narrow it down!