Don't laugh, but this only cost me $2.43 at Ace Hardware....lol
Took our cat scratching post that the cat never used...turned it upside down, used some self-tapping wood screws to secure the joystick base plate to what was the base of the cat scratch post. Then drilled a hole in the center of a 12 x 12 piece of plywood and screwed the top of the post into it and secured it with a 7/16 nut. Don't forget, to remove the cap off of the top of the post..it easily screws off resulting in a 7/16 bolt showing.
https://www.dropbox.com/s/i3j69o1qiy5esk8/2018-06-02%2017.57.37.jpg?dl=0