Pandaren Champions can drop a satchel (containing linens, jewels or skins), a piece of armour as well as a special item. Although the ones in lower-level zones drop a Small Bag of Goods instead.

The fun items and satchels do not appear to be a 100% drop.

Arness the Scale

Sandy Shallow peninsula, south of Ruins of Dojan

Cournith Wavestrider

Inside the big building in Fallsong Village

Gaarn the Toxic

Standing in front of a tent in the Ruins of Dojan

Go-Kan

Sits on a boat in the middle of a pond

Qu'nas

Krasari Ruins

Ruun Ghostpaw

Inside the Temple of the Red Crane

Spriggin

Walks around a shipwreck on top of a hill in Unga Ingoo

Torik-Ethis

Found in the Forbidden Jungle