I came up with
I tried 8(), but decided that looked too much like a frog.
There is D: but I decided that's too emotionally loaded. 8-() has that wide-eyed quality you get with O.o (and its twin o.O), plus it has a stunned quality I like.
My apologies to any of my readers who have NO FRICKIN' CLUE WHAT THE HECK I'M GOING ON ABOUT. (Maybe this page on emoticons will provide sufficient context...)