Well being a Skinner myself with a skill of 279, I think you should beable to get the scales off any of the Dragonkin. The area that i know where i had gottin one was the area just above Wetlands. But they are a rare drop just like the Turttle Scales. I hope this helps ya bit.
"Knights ofthe Blood Oath" Guild leader on Magtheridon. Also Dragonscale Leatherworking 255
Skinning 297 and Cooking 254