micro synths aren't 9 volts, I think they are around 12? I'd have to check mine... you Should be able to get away with a wall wart adapter, trying it shouldn't hurt your pedal... you can also buy a UK adapter for it. Otherwise you'll have to get a big ol power converter..... look online for the appropriate adapter then sell the US one to someone.
edit (I see the new microsynths take 9volt) if you have a pedal power or something similar it should jjust plug in, just buy a 9 volt adapter and it should work fine.
you can get a proper one here: http://www.ehx.com/products/96v-ac-dc-power-supply