Note: Farmed this NM for Trial 838 and got the Bottled Pixie 10/10. For Trial 1700, however, I reached 6/15 before he decided to stop dropping them. 4 kills in a row, the Bottled Pixie did not drop.
Castle Oztroja @ (H-9) When you walk in the main room take an immediate right. The hallway/tunnel straight ahead is a safe place to fight a Yagudo High Priest that spawns nearby. Used this when above camp was being camped others.
Note: Good idea to dispel the yag a few times to take of stoneskin, blink, shell, and protect. Made it easy to kill with 3 nukes on my BLM/RDM with no need to rest and you can Aspir II for a nice chunk of mp.