A couple months back my 2 year old 13" MacBook Pro’s power adapter fizzled into oblivion while in the middle of working on a project. And thus began the quest for a MBP power adapter. Coincidentally lots of places were out of stock (AV, Yihfa, Dee Jay) or required a custom order which would take several days and thus I even considered knock-off power adapters from B.I.T. The next step was looking up if other Apple laptop power adapters would work to replace my 60W power adapter. AV did not recommend using a 85W power adapter for 15" MBP on my 13" MBP but after looking things up online it seems fine: the main take away is to ensure the same voltage but higher or equal amperage. Even Apple says a high wattage (voltage*amperage) power adapter is fine (via StackExchange: "Can a 60W MagSafe power adapter work interchangeably on a Macbook Pro that “requires” an 85W adapter?").
Surprisingly enough, I found my power adapter at Incomm at the Mall as I randomly just walked in to look a some phones.