Cockroach

About 59s 0c on Beta · Horde (5 hours ago) and 69s 0c on Beta · Horde (23 hours ago), from player scans. A vendor pays 12s 50c, so the auction house pays 4.5× 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 56s 5c there, against 12s 50c at a vendor.