During The Burning Crusade, Fel Armaments and Marks of Sargeras were good sources for WOW gold. You might think that those days are over once Wrath of the Lich Kings arrived but in reality it is still worth something. It might not be as good as before but you could still profit from it.
There is still a market for Fel Armaments and Marks of Sargeras these days. Death Knights going for achievements would still want to get exalted with the Aldors. Plus, there are still some people who might not have encountered the Sons of Hodir yet.
As it was during the Burning Crusade, the best spot for me is located at the Legion Hold of the Shadowmoon Valley. Even a decently geared level 70 can make minced meat out of the Shadow Council Warlocks with their 5k+ HP. Plus, you will not run out of them because of their fast respawn rate. Just be careful of the wandering elite but a max level character can easily take care of those elites.
Not only will you be looting Aldor rep items but you’ll be getting lots of Netherweave cloths as well. This cloth is still in demand as well with all the Death Knights leveling their First Aid skills. And don’t forget the Tailors who require this type of cloth for their crafted items.
You could also try the Arklon Ruins in Netherstorm. This would be a good spot if you’re a skinner. The Artifact Seekers found in the area can be skinned for Knothide Leather. These are easy kills and in just an hour you can loot around 1 stack of Fel Hide, two to three Fel Armaments, 30 to 40 Marks of Sargeras, and a couple of greens. Manacasters though show be aware of the manaburn these mobs are capable of doing.
If you’re looking for Scryer rep items, then go to the Southern ramp before going to the Black Temple. You’ll know you’re there when you see lots of Black Elves lined up waiting to be killed. These mobs have a decent respawn rate as well. You’re only downside would be going back to the bottom of the hill once you’ve killed every single one of them.
Aldor and Scryers might be the thing of the past but they can still be worth something. Check your Auction House to see if there are competitions in this market. You might be lucky if you can have the monopoly for these in your server.