Intact Basilisk Spine

About 20s 0c on Beta · Horde (2 days ago), from player scans. A vendor pays 3s 20c, so the auction house pays 5.9× more.

No. It is in Classic Era too, with the same item level, vendor price and stack size.

Sell it on the auction house. After the 5% cut a stack of 5 brings about 95s 0c there, against 16s 0c at a vendor.