Destiny Emblem Collector is the most complete source for Destiny emblems: what they look like, exactly how to get them, and whether they're still available.
DEC currently tracks 809 Destiny 2 emblems and 271 Destiny 1 emblems.
Iron Banner is currently live! You can get past Iron Banner emblems (except Heavy as Death) as possible end of match rewards.
You can see all the Iron Banner emblems in the Competitive category.
Legendary - General
Legendary - Competitive
Common - General
Legendary - Raids