We're moving back to Europe...
Used, but in excellent condition. Stand included, but not the adapter (missing). You can get one here for example ($ 10) :
http://www.ebay.com/itm/AC-Adapter-For-Yamaha-PSR-500-PSR-500M-PSR-510-PSR-262-PSR-4500-PSR-50-Keyboard-/?pt=Laptop_Adapters_Chargers&hash=item20d5d0eb57