Big and tall clothing

I need some help. I have lived in Belgium for a while now but have never bought clothing here. I am a big and tall man (6´5" and 260+). I don´t like to shop online because I like to try on what I am buying, and maybe I was spoiled in the US with discount retailers, but I have been putting off buying new trousers because of the prices here. Unfortunately, most of my trousers have fallen into such disrepair that I am in desperate need of trousers. My suit pants ripped on Sunday from buttock to knee, not along the seam by the way.
So does anyone know of a place near to Brussels or Leuven which sells big and tall men´s clothing for decent prices?