You could probably make a portable single post and support it with guy lines and tent spikes. But I still think the simple wooden tripod is best for economy and ease of build.
Here is my rig. It is made from steel strut like the weldless brew stand concept. I then have a black piece of conduit from the Home Depot like $10 bucks. Added a 90 degree angle and a smaller piece and then drilled in my hook for the pulley. Have a few mounts on the side where I can put the pole in when I need to pull the bag. Then I can remove the pull and roll it out of the garage to begin the boil. If you want a closer picture of how it attaches can send one after work.
He mentions "black" conduit....the pic looks like black iron gas pipe, that's pretty heavy stuff, nothing like Thin wall EMT. Or electrical metallic tubing.
Perfect.