If you want all the top tier items then you need to kill certain animals. These animals can only be found on the Path of Hunter side quests. Here's what you need to kill:

Albino Crocodile: Extended rocket pack.
Horn Hide: Extended wallet.
Black Panther: Extended syringe kit.
Blood Komodo: Extended grenade pouch.
Golden Tiger: Extended ammo pouch.
Man-Eater Shark: Extended arrow quiver.
White Belly Tapir: Extended munitions pouch.
Yellow Neck: Extended fuel sling.
Undying Bear: Extended rucksack.