Internal widths of the Tracsporter XW is 6' -1"
The Prosporter models are XWN 6'-11" and for the XW is 7'-5"
all info here:
http://prgtrailers.co.uk/index.php/trailers/prosporter.
They look expensive, no indication of price given not even a basic starting price, which would suggest that they are built to order and individual specification.