A great place to farm the Balaur in Upper Abyss is west of Asteria Fortress. To the west of Asteria Fortress you will find a large island covered in Balaur. If your gathering skill is high enough you will also find a lot of Platinum and Garnet here as well. The Balaur are 33-34 so any level 32-33+ will easily be able to kill everything here.
On the western side of the Island watch out for an elite that patrols around. She isn't a joke. At this camp you will be farming for/getting the following items:
Pure Platinum Ore
Greater Platinum Ore
Big Garnet Ore
Cold Balaur Blood Stain
Thick Balaur Horn
Tough Balaur Meat
Vicious Mind of Wrath
These items are used in various Tradeskills and will usually net you a pretty penny in the AH if you don't choose to use them for your own crafting. Also on another plus note the Balaur here do drop Kinah as well as all of these items. This makes you feel better if you're getting unlucky and not many extra drops.
NOTE: Around level 43 these Balaur will stop dropping loot because your level is too high.