This quest is not available in game.
Bring a Shadowcraft Belt and a set of Shadowcraft Gloves to Mokvar in Orgrimmar.
You've proven to be a very reliable individual, <name>. As much as I trust that you'll help me through this predicament, it would be wise of me to reward you according to your performance.
For now I will exchange your belt and gloves. If we both see this through I shall make the rest of the pieces available to you.