heavy armor

I have traveled far and wide in Calradia, several times, and I can say that it's almost impossible to find the best armours, but also only good. It is so frustrating...

How do towns produce armour? Is it related to town's inventory or shops in the town? Because town inventory, especially armors they sell never seem to change. I am filthy rich but I can't find high end armors in towns and apparently they remained same since the very beginning of the game.