3 Barbarian only items to spice up your treasure!

[Machiknight]

Battlepaint of Burning Rage
Wondrous item, uncommon, cannot be activated unless owner has the Rage ability
A magic pot filled with the kind of paint that the Berserker uses to make themselves look more fierce in battle. When the berserker goes into a rage any opponent that makes a melee attack against him suffers 1d4 points of fire damage. If the Berserker is in a Frenzy, the damage is increased to 1d8. The effect lasts until the rage is cancelled. The pots usually contain enough paint for 5 uses, but some may be larger or smaller. Application of the paint takes 5 minutes.

Spirit Token
Wondrous item, uncommon, cannot be activated unless owner has the Totem Spirit ability
A small piece of your totem animal, a claw, a tooth, a feather etc. It has 3 charges and recovers 1 charge per day. Using a bonus action the Totem Warrior may summon forth a spirit version of its chosen Totem Spirit. The Spiritual creature immediately makes an attack on a target of the Totem Warriors choice, then disappears back into the astral plane.
Bear - The bear charges out and slams into an opponent, forcing them to make a DC 14 Dex save or be pushed 10ft in any direction.
Eagle - The eagle swoops directly toward an opponent that is using concentration, forcing them to make a DC 14 Wisdom save or lose concentration.
Wolf - The Wolf leaps onto an enemy forcing them to make a DC14 Str save or be knocked prone.

Battlekilt of Frenzied Focus
Wondrous item, uncommon, cannot be activated unless owner has the Frenzy ability
This stylish kilt gives it’s wearer the ability to become intensely focused on a single enemy. When the Barbarian enters a frenzy she chooses a single enemy on the battlefield and her movement gains 10 ft as long as it is used to move in the direction that opponent. All attacks against this opponent also gain +1 to hit and damage.

[WicWicTheWarloc]

I am loving the paint item. Simple to the point. Maybe have the application time increased? But I've never been applied with war paint so I don't know how long it takes.

For token spirit since you only get 1 charge a day you should buff a few things. For the bear they also take 1d4 bludgeoning damage just from the bear hitting them. For the eagle they also take 1d4 slashing damage. And for the Wolf have them take 1d4 bite damage. I feel like no damage on a 1 charge refill is a bit of a cheapy.

I also love the kilt. I don't have any suggestions for that. Maybe perhaps as a bonus action they can choose to moon the creature first?

[Machiknight]

as a bonus action they can choose to moon the creature first?

Haha I love this.
Bonus action, moon creature for a +4 intimidation check.