Another option is to focus on getting Dream Dust. While doing that, you'll probably get some Nether Essences to help you up a few levels. HINT - get a tailoring friend, and you can just farm cloth (Mageweave is easy to farm in Hinterlands - Jintha'lor or the AH)
Then, once you hit lvl 265, get the
Enchant Shield - Greater Stamina recipe. 10 Dream Dust per enchant. That will get you from 265-290 easily.
The hardest part (I found) is when you need illusion dust or eternal essences. Those are the toughest to come by, even working the AH...
EDIT - farming instances at that level are hard. They go kind of slow, and the only reliable drops are the blues from bosses. As you know, those will give you shards most of the time. Shards are not very useful while leveling, and don't sell for much money (other than Prismatics of course).
Edited, Apr 23rd 2008 10:57am by YJMark