If you're visiting Wilmington, drop by the Five Star Tavern. The owner, Adrian is an exceptionally nice guy running an exceptionally friendly watering hole and he's got a couple of machines. He's even setup a league, quite a hoot. I chatted with him one evening and he said he's learned more about skeeball machine repair than he ever cared to
(Might explain why you don't find too many machines out in the wild)