FET AMP POWER SUPPLY
 

I want to power my FET amp(200W) from a mobile power supply. Amp requires
50VDC. It occured to me that car stereo amps use DC to DC converters that
would produce the voltages and currents that I need. Would like information
on where I could get parts/information to roll my own. I am particularily
intersted in the transformer design and where I could get one already made.
This doesnt seem to be something one can get easily as a replacement part.