Thomman in Germany are replacing my power adapter under guarantee with a equivalent yamaha replacement viz.....
PA-130, thomann PA3C
Thomann NT 1208, switch mode power supply, 12V 1000mA, stabilized, DC Yamaha mini (PA-130, thomann PA3C)
http://www.thomann.de/gb/gewa_coxx_1208.htm
yamaha also do a 3 pin UK version of this plug.