BulletLukey has made an awesome world for this. You can join our realm (as long as it still runs) or download the world yourself.
In this world, simply go to the update 1.10.0 area, and retrieve all the 3 items from the chest. Then interact with the block, place the stencil, dye and banner in their corresponding spot. Then make a couple of banners. If it doesn't pop try placing a few of them on the floor.