Which type of Ethernet magnetics should I choose for PoE?
TLA-6T127LF(-T)    supports POE in stock.
http://www.digikey.ca/product-detail/en/TLA-6T127LF-T/445-6788-1-ND/2523609

But the extra coil can be terminated to ground. But no problem if open as it is common mode without much different load.