The Astrologer Quartermaster in World of Warcraft is a camp NPC and cannot be obtained. If you are asking how to unlock it or how to buy things from him, then you only need to complete the task of joining the Astrologer camp and join.
Answer: Unable to obtain
He is an NPC in the game and cannot be obtained, only unlocked.
1. If you want to unlock the Astrologer Quartermaster, then just join the Astrologer camp.
2. To join the astrologer camp, you only need to complete the " Work for the astrologer " task.
3. First go to Shattrath City to find Khadgar (54.8, 44.3 ) to receive the mission.
4. Then follow Khadgar's servants to tour the city, and then go back and deliver the task to complete the task and join the astrologer camp.
5. After joining, you can purchase goods from the Astrologer Quartermaster.
PS: Joining the astrologer camp will cause Odor's dissatisfaction.