The suit is not an exact MOD style of suit. It is a slim-fit, however it is a 2 button single breasted with side vents in a 3.piece. Note the real button cuffs and the real horn buttons. It also has a monogram inside and a fancy two-tone lining & white striped sleeve lining.
My GTS300 was purchased at the wonderful STEADS in Romford: http://www.steads.co.uk/