The backup on iCloud is for Restoring an iOS device. Time Machine is your best otpion although Apple has it messed up a little here as well on Mountian Lion. Read https://discussions.apple.com/message/19171700#19171700 for tips on loacting the folders then enter Time Machine to see if you can recover the notes. I found for the most part though old note are not recoverable using Time Machine as well. I'm suprised this has not been fixed yet since it pretty much breaks the whole idea behind Time Machine.
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