Does this model's keyboard replacement also work on a mid-2012 model?

Sadly, Apple does not sell the keyboard alone. The newer models also have a mix of screws and snap rivets (aprox 50) so its a bit of work just to take it out.

Some people have managed to locate the manufacture of the keyboard in China and have imported the keyboard part alone.

Frankly, I recommend just replacing the full upper case Vs fighting with the screws let alone having to tap out the holes of the rivets you break for screws which you then need to locate to fit the tight space. If you don't replace the rivets your keyboard will feel very spongy as it sinks as you type.