Nobody's noticed this yet, but the guide I posted is for the MacBook, not the MBP.
Anyway, it doesn't look like it'd be too difficult to do, if you're willing to void the warranty. Personally, I wouldn't hesitate, looks a lot easier than the 12" PB HD that I replaced a while back, and it wouldn't have to be shipped away/left in a store for... however long it takes.
At any rate, this surgery would have to be performed by an Apple-certified tech, but the prices are totally up to them. I'd bet the service charge would be somewhere in the range of $100 or so.
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