The path of least resistance for getting this is obviously the bazaar, but if you ARE going to farm it I highly suggest Tipt.
Go to guild hall->barindu the hanging gardens. Go to north east and talk to Apprentice Udranda. Say titpt, then go to the "broken zone in" just east of her.
Once inside Tipt, its a straight hallway. Kill any cragbeast you see. Youll come across a big opening where a ton of little crags spawn, then a big crag. After they are all dead, alt-z and quit the DZ, it will boot you, re-do it. Simple, but time consuming.