Need a Signet of Capture

I am looking for an NPC which sells the Signet of Capture any one got any ideas

Ive just picked up it up from a quest either from Druids overlook or the one before (forgotten name soz) at that point anyway.

Not managed to find an elite mob yet with warrior skills but hey..

Magi in Lion's Arch who gives the quest for the signet also sells them.

Also, skill trainer in quarrel falls has it