This item is acquired in-game. See its sources below.
In the Appearances collection, Artist's Sash is listed as Quest. Appearance ID: 70237. 8 other items wear the same appearance:
Read from the World of Warcraft client build files.
Mail is the armor type Evoker, Hunter and Shaman wear. With Agility or Intellect, Artist's Sash suits Beast Mastery, Marksmanship and Survival Hunter; Elemental, Enhancement and Restoration Shaman; Devastation, Preservation and Augmentation Evoker.
Artist's Sash is part of the transmog set Trailblazer's Mail Armor (Hunter, Shaman and Evoker only). The other 16 pieces:
Expedition Mercenary's Legguards
Expedition Mercenary's Grips
Expedition Mercenary's HelmExpedition Mercenary's Leggings
Expedition Mercenary's MonnionExpedition Mercenary's Belt
Expedition Mercenary's Bracers
Drape of the Djaradin Slayer
Expedition Mercenary's Boots
Expedition Mercenary's HauberkWasp Repelling SkullcapEarth Binding ChainExpedition Mercenary's WristwrapsSister's GiftTime WalkersChronomental GlovesBuilt from the World of Warcraft client build files and recorded Auction House snapshots.
Artist's Sash is not traded on the Auction House, so it has no Auction House price. It is acquired in-game from the sources listed above. This page collects its first-party game data (identity, effects and where it comes from) from the official World of Warcraft client build.
TheWoWDB