That's some really good info. There's a local operator here who just opened a "shop" to sell "restored" games, which means easily $500+ each I'm guessing, but I haven't been by there yet.
Ebay, believe it or not, has been the best bet for me. In the search functions of ebay, you can see who's selling machines within a specific radius from where you live. I myself am usually willing to drive no more than 250 miles one way to get a machine, if the price is right.