Long time ago there used to be a company that sold treestand hunting umbrellas in dark camo pattern. Essentially they were just regular umbrellas with one rib missing and were sold with a bungee cord that you wrapped around the tree and over the umbrella handle and could be set up quickly and easily. I bought those from Wing Supply but eventually they quit selling them.
The newer umbrellas are a different brand and are the ones that you have to screw a mount into the tree then attach the umbrella on that mount. I have one of these and it works OK but is small and I prefer the other set up better.
Buy a large golf style of umbrella in your favorite color combination, remove one rib so the umbrella can be placed tight against the tree, wrap and hook bungee cord around the tree and handle, and you are set. One of these in a camo color can double as a ground blind in a pinch also. Just set it up, lay on the ground, and get behind it. To carry I slide it under my belt on back side or just leave it in the stand for the next hunt.
Hope this helps.
Dave1