63 leather trade goods items
The Forever catalog holds 63 leather trade goods items, topping out at item level 63 with Dreamscale, Core Leather, Fel Hide. Every crafting material in the game: herbs, ores, bars, cloth, leather, gems, enchanting materials, and reagents. The supply side of the whole crafted economy, with prices and 7, 30, and 90 day history per market.
By quality: 54 common, 5 uncommon, 4 rare. Item levels run from 1 to 63. 1 bind when picked up and never reach the auction house; 62 can be listed.
The highest item levels here: Dreamscale (63), Core Leather (60), Fel Hide (60), Fel Leather (60).
Professions make 13 of them: Leatherworking (11), Alchemy (1), Enchanting (1). The rest drop, are sold by vendors, or come from quests.
Source: World of Warcraft: Forever game data and Blizzard's Game Data API. Updated with each game build.