Is it possible to put inside the bluetooth keyboard?

BlueTooth is built into the laptop so if you "pair" (match) the devices they will work... FWIW I've never read/heard about a Macintosh BlueTooth laptop keyboard.

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No... I have tons of those 1314 keyboards and they are destroyed once you pull at the back of them. Further, the connection point does not match up that I am aware of.

The best option is to get a new top case that has been completely taken down to bare bone. You can find them on ebay with no touch pad and just a keyboard.

The process is simple if you follow the tear down guide on ifixit.

MacBook Pro 13" Unibody Mid 2009 Repair

I have not attempted the keyboard removal but RDKL on here has. He posted that it had something like 100 tiny screws that hold the frame to the top case.