Our MoP Classic item table (the Blizzard item records our Auction House scanner has collected) has 10 other mail waist items between item level 339 and 377; 8 of them carry fixed stats.
Cheapest listed mail waist items at a similar or higher item level: Saurok Belt at 20 gold (item level 364, requires level 83), Steppe Belt at 50 gold (item level 377, requires level 84), Vicious Dragonscale Belt at 556 gold (item level 377, requires level 85).
Connected realms with a listing in the latest MoP Classic scan: EU 0 of 25, KR 0 of 5, TW 0 of 8, US 0 of 23.
Item data: MoP Classic client datamine, build 5.5.4.70631. Prices: per-unit buyouts from one Blizzard Auction House snapshot per connected realm per hour; market is the quantity-weighted median of a realm's listings. Retail column: the retail client datamine.
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