Emile's Restaurant, 545 South Second Street, San Jose; (408) 289-1960
www.emilesrestaurant.com is another option and it has 2 private rooms although the banquet menu is a bit higher than you requested. Its "bistro" offerings would match your range. I don't think the quality (food or service) has been quite as good since Emile Mooser sold it about a year ago.
If you can up your price point to <$30 for entrees, Gervais Restaurant in downtown Saratoga is pretty good. The lobster bisque & asparagus soup were both delicious, as well as the foie gras - seared & terrine. My husband said the duck was ok, and I thought the quail was pretty good. The chocolate souffle was yummy as well! Be sure to order it w/ dinner if you want it, as it takes 20min.
They had a small private room that fit m/b 10 or so people... The restaurant is in an old Victorian house, so m/b you could one of the rooms for your party if the private room is too small.
14560 Big Basin Way
Saratoga, CA 95070
Phone: (408) 867-7017