There are all kinds of articulating mounts intended for flat screen
tvs that might work for your application.
Wall Monitor Mount | Black Extending Bracket for Flat Screens
is one that I found. Amazon.com has all sorts of them as well. I am doing this same thing for my boat to mount a tablet PC to run OpenCPN
viewable from cockpit and then swing back into the cabin
and be used for the other functions that a tablet allows.