Scott's Outdoors in Jay, FL sells a really nice custom built box blind. They are fully sealed in all seams and window frames with insulated foam. I have had deer 10 feet from me downwind for minutes at a time and none have smelled me. My only complaint is that they are loud when you bump the sides or move around in them. But a little carpet on the floor and some adhesive felt in the right places and they are quiet. I seem to recall they are made somewhere in Alabama. Maybe give them a call if that might be what you want.