Since pachinko machines were originally mounted in the walls of pachinko parlors, they need to be supported so they don’t fall over. The simplest solution it to screw or nail a couple of boards to the bottom of the pachinko machine. Just about any scrap boards you have will do. Pachinko Restorations sells boards that have routed edges and a nice finish; they are 1” x 4” x 10” also sells cabinet plans.
A more secure solution would be to construct a table top cabinet, floor stand cabinet or wall mount cabinet. You can view pictures of various stands and cabinets that people have built below. Pachinko Restorations also sell cabinet plans.
Links to other cabinets websites without recommendation!