You could go with a watch...I got my GF one of these burberry watches used off of ebay pretty cheap for our anniversary last year. I know they aren't very high quality watches (I believe fossil makes them) but they look pretty good and have a luxury brand name.
http://www.ebay.com/itm/Burberry-Heritage-Womens-Silver-Round-Face-Bracelet-Watch-/281106483673?pt=Wristwatches&hash=item41734089d9 Also if your gf is anything like mine and doesn't know anything about watches she wont mind that its made by fossil.