Many online retailers sell products until they run out, and once they're gone they're gone forever. We need a way to reflect this in our database, since at least one retailer is autoselected as "purchase for mail-order." VGMdb has an "OOP" (out of print) check box in the "Manage links" interface that lets editors mark that release as no longer available through that retailer. This is a good idea for MB, since at least one retailer that I can name is autoselected as "purchase for mail-order."