The 399 Borders Books and Music stores that remain open could start closing as soon as this Friday, July 22. The company did not receive any offers from buyers that would keep it in business, so it goes back to federal bankruptcy court Thursday, probably asking for permission to sell its assets to liquidators.  Borders closed its King of Prussia Superstore and several other stores earlier this year, but kept the one at the Airport Square Shopping Center in Montgomery Township open.  That will close now along with 13 other stores in Southeastern Pennsylvania and Southern New Jersey.