Big Bronze Knife

About 30s 0c on Beta · Alliance (17 minutes ago), 34s 0c on Beta · Horde (6 hours ago), and 38s 0c on Beta · Horde (24 hours ago), from player scans. A vendor pays 14s 26c, so the auction house pays 2× 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 1 brings about 28s 50c there, against 14s 26c at a vendor.