Cat Carrier (Siamese)

About 20s 0c on Beta · Alliance (1 hour ago), 27s 0c on Beta · Horde (7 hours ago), and 35s 0c on Beta · Horde (1 day ago), from player scans. A vendor pays 15s 0c, so the auction house pays 1.3× 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 19s 0c there, against 15s 0c at a vendor.