Thanks guys for the comments, very much appreciated as some of the info gives me some direction.
In the end I would not do it intentionally as a business to survive from, merely one that I can combine my passions together and maybe there is an opportunity to cover my costs and go from there in the future.
I will definitely start by contacting Steve Young and go from there re the surf champ playfield and learn from there, you just never know.
I have also a few other Pin-gineering ideas to concept out, and will share in good time if it works.