By 2 of any cheap low voltage transformer - say, something with 12V secondaries.
Then connect them back to back (i.e. 12volt winding to 12 volt winding). The whole setup then makes a 230 to 230 V transformer.
or
buy one, but run it backwards, feeding the 12Vac 'primary' from a cheap ac plug pack power supply. You can rectify/regulate/drop the 12vac directly for heater supplies as well.