Usually they will have sandblasted manzanita or grapewood branches. Find a big tall grapewood branch to put vertically (or a few smaller ones and attach them together) and some manzanita branches to put horizontally.
Buy a bundle really cheap. And you can dye them with natural dyes if you don't like the bleached manzanita branches.
Also, any wild branches found WITHOUT lichen, mold, fungi, and other growth should be fine if it is found dry.
I like buying/finding my own branches because they look cooler than twisty jungle vines covered in grainy stuff.
When you find branches in the wild, turn an oven on 350-500 degrees f, when it heats up, turn the oven off and leave the branches in for 5-10 minutes, killing bacteria. Some people think it is unnecessary but it's a good precaution.