Hello,
Thank You for inviting us to your project.
We are developing games for past 5 years and have proficiency in Unity 3D.
We have created many Video Games in Unity 3D of different genres like Shoot 'em up style, Racing, Casual, 3D Endless Runner, 2D Platformer for different platforms like Android, iOS, WebGL, etc.
Well the time frame will depend on the game concept but for Casual Games 10 days will be enough.
We will definitely help you in deploying it in playstore or in other management process.
Please, contact us to discuss further details.