Common mode chokes in series
There is rather more too it then that, high Z common mode chokes (Large value inductors generally really) tend to have resonances at surprisingly low frequencies, so details matter. 

What does spice say (after you have added all the parasitics!), and what numbers are you trying for? 
Design is a numbers game, once you decide what noise over what bandwidth you can live with and what the supply impedance limits are, you can start designing, but decide what your criteria are first, otherwise how will you ever know when you have it done?

I have designed some high end pro audio kit for a living, and trust me DC-20KHz with a 110 odd dB of dynamic range? Meh doesn't really take a special power supply to pull that off, board layout is a ton more important (I use XP Power 2 by 4 inch switchers, right combo of universal input, cheap and reliable, do it right and you cannot see any residual in the FFT of the output).