When we had our son christened, we were told that you weren't supposed to get the godparents anything... I decided to go with photo of Henry when he was born and one of him taken a few days before his Chistening. I got on the computer and made the photos wallet sized and laminated them back to back. This way they can have a picture of him on hand at all times to show off!!
They loved it and I hear from Henry Godfathers parents that every where he goes, he shows off his godson....he adores it. And his godmother wont put it in her wallet in case she loses it!! She keeps it beside her bed.
I think something small is fine. As long as it comes from the heart... Maybe if you want to go further than that, my first thought for Henrys godmother, who is my oldest friend, was a locket with a picture of Henry in there and I was going to get a picture of her fiancee to put in there as well...
I don't think it really matters what it is or whether u spend lots on it, as long as its special to you and them, that will be the best...
Hope that helps.
Liz, 28, DF, 29. Henry- 18/10/2006, Faith 5/6/2013, Peanut being induced 21/10/2014.