for those wanting T5 chest but having trouble with Kael'thas.
just grind out 1,000 honor and buy the merciless gladiator chest from the pvp vendor in area 52, they are the same model, just the pvp set is slightly darker in color than the pve T5 set.
i was able to collect tokens for the chest, hands, and shoulders and bought the helm for 1k honor (using the arena season 2 lock set)
icy-veins.com/images/transmog rification-warlock-pvp-arena- season-2.jpg
take the spaces out of the url link