Need help rigging and animating a face

I have purchased the following model from TurboSquid:

I have made some modifications to this model, mainly removing most of the internal geometry (I don’t think robots need teeth and a tongue) but the outer appearance is the same.
I need to have it rigged and animated for smiling, frowning, talking, eye movement, blinking and eyebrow movement. I am planning on using this in the Unity3D game engine so it needs to only use bone based animation, no shape keys. I have tried to do this myself but I have not been very successful. I was able to get jaw movements but real facial expressions I was unable to do with my limited Blender knowledge. I am wanting something similar to the rig at or the Othello rig if possible. Would anyone like to help me with this? If so, please PM me and let me know how much you would charge. If you need any other information let me know.