transformer supplier for half bridge SMPS

[jegandren]

Hi,

I am doing a half bridge switching power supply, at the moment i would like to purchase the transformer and the spec as below:

Topology : Half bridge
Switching Fequency : 100Khz
Input primary voltage : +/- 200V
output voltage : 25V
output max current 12A
Core ETD 44
output Power : 300W

Could anyone suggest me a supplier for this transformer spec..

Thank You