Actually, this is the only option for purchase (or preorder) I've seen for the USA online.
It's a $9.95 download version from Ubisoft USA that says it will be available for download on the 28th. I thought this game was coming out here in the USA today, on the 26th? Either way, I want a nice boxed hard copy.
http://digitalstore.ubi.com/178/5867/product/Buy-Silent-Hunter:-Wolves-of-the-Pacific-U-Boat-Missions-(Pre-Order)-Download