Our MoP Classic item table (the Blizzard item records our Auction House scanner has collected) has 45 other mail chest items between item level 21 and 39; 24 of them carry fixed stats.
Cheapest listed mail chest items at a similar or higher item level: Reinforced Chain Vest at 45 silver (item level 28, requires level 23), Glimmering Mail Breastplate at 88 silver (item level 31, requires level 26), Phalanx Breastplate at 99 silver (item level 35, requires level 30).
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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