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Something like this, probably.
3308.jpg

http://www.bagbliss.com/images/handbag/3308.jpg
 
Good luck honestly. Target sells a case made by Moda for $10 and that may work for you. It's a pretty big case.
 
Eddie Bauer XL sideways case, I got one at Bestbuy, it's advertised for the droid x and phones bigger than the iPhone. There is a smaller version, but that will only fit a naked iPhone or one with a smaller case on it.
 
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