Bikes for big people

After visiting Mercian to get fitted for his custom tourer frame, they have informed my dad that they cannot make a frame suitable for someone his size (height & weight).

Does anyone know of any uk based frame builders who can make large strong frames? My dad is 6'9" and weighs nearly 290lbs.

Lazy. Probably couldn't be bothered getting the calculator and ruler out...
That or they have a fear of long headtubes...