So far the following loot is known (source - MMO champion).
Storm Tempered Girdle - Razorscale (3rd boss)
Legacy of Thunder - Thorim (10th boss)
Archaedas' Lost Legplates - Auriaya (7th boss)
Cloak of the Iron Council - Iron Council (5th boss)
Signet of Winter - Hodir (11th boss)
Shield Wall of the Breaker - Auriaya (7th boss)
There is also hard mode loot, loot which is listed as "unknown" and so will presumably drop from other bosses, and tier 8 tokens to consider.
I didn’t realize how old I became
10 hours ago