simplysitting.com makes beautiful and portable meditation benches, that I was not quite able to buy. So I made mine from easy to find parts. I haven't tried theirs, so I can't say how mine compares.
Step 1: Parts & Tools
Step 2: Assembly
I cut my dowel to 6 inches which brings the overall height of my bench to 8.5 inches. I may change this over time. The Simply Sitting bench is 7 inches tall.
I then inserted it into the seat post hardware and tightened it so the post is perpendicular to the seat. I may change this over time as well.
As it is, I can't easily remove the post, because the hardware must be tightened to prevent the seat from tilting and collapsing. If later I want the post to be removable, I will loosen the hardware and JB weld it in place, leaving the post receptacle just loose enough to insert and remove the post.
I will also probably decorate my bench, its currently not a very uplifted object, but it is comfortable.