Hi, I have an acoustic, I want a small "plate" tuner that i can install in it (IE cut a small hole in the side and install it.)

I cant find such a contraption, all I can find is complete acoustic pickup systems that have a EQ, tuner pickup etc. All I want is the tuner, and a small a one as possible that i can install in the guitar.

If anyone knows of such a product could you point me in the right direction?

RG's & Mesa's