Most of the eBay SONY's are made in China. If you want a real one buy it from SONY. My solution was to buy the Macaly I-481 battery pack which will allow you to burn something like 20 Hi-MD's. It is a Li-Ion, charges from the SONY RH1 charger or from your USB port, is small and can be had in matching black. And it costs little more than the SONY battery from SONY. Lot's of help on this and other MD problems is available at minidisc.com, a board focused on MD.
Cheers