Sugi's Kasa Hat belonged to a well-known former raider. You can only collect it after finishing the side tales "Troubled Waters" and "Bloodletting", near Thieves Rest Lighthouse.
Complete "Troubled Waters", then "Bloodletting". Go back to the village by Thieves Rest Lighthouse to find the hat.
The hat is on a body tied to a tree in that village.
Yamaneko's Eyepatch
Yamaneko's Eyepatch is an eyepatch from Iki Island that once belonged to the raider captain Yamaneko. You can only claim it after two side tales, then a trip to the Shattered Cliffs coast.
Charm of Descending Talons
The Charm of Descending Talons is a minor Melee charm from the Iki Island expansion in Ghost of Tsushima. Jump attacks can stagger and knock enemies down, and the higher you drop from, the more damage you do. You get it by finishing the tale Bloodletting.
Charm of Fleet Foraging
The Charm of Fleet Foraging is a minor Utility charm from the Iki Island expansion in Ghost of Tsushima. Melee kills have a 15% chance to give back quickfire ammo. You get it by finishing the tale Troubled Waters.