Commercially-bought bar stools tend to be either poorly-made or poorly-designed. Why spend a few hundred dollars on a mass produced product which probably skimps on the molybdenum content of the steel, when for a few thousand you can commission an iron monger to produce a stool to your exact specifications?

Yes, good iron-mongery is harder to find these days, but I find it worthwhile to develop a good relationship with local craftsmen. They can also be useful for when you need gateposts, horseshoes, arbors etc.