In Wrath of the Lich King it is item level 251 and requires level 80. In MoP Classic it is item level 251, requires level 80 and sells to vendors for 1c.
In the Appearances collection, Relentless Gladiator's Redoubt is listed as Vendor. Appearance ID: 9765. 16 other items wear the same appearance; 2 of them are listed here.
Items Numbered Next to Relentless Gladiator's Redoubt
Blizzard numbers items as they are created, so the named items next to ID 42572 (42566 to 42578) were usually added in the same batch as Relentless Gladiator's Redoubt: the same quest line, zone, vendor or reward set.