How to pick a Push-Pull Transformer?
Consider winding your own: - 

The coiltronic spec tells you the primary inductance and turns ratios. Choose a ferrite that is lowish loss at YOUR operating frequency. The ferrite chosen will have an A(L) value which basically tells you how many turns you need to wind to get the inductance of the primary. Secondaries are factored from the primary turns with the turns ratio.

Notice the voltage testing they have done to prove the isolation - this can be emulated with layers of polyester or PTFE tape or maybe consider a toroid where the windings are spaced apart BUT the ferrite is still potentially conductive so you will need insulation but only half the amount per winding.

Once you have got your head around this it will allow you review other manufacturer's offerings.