Yes, it's a real ST. Sea grey was an option colour for the ST in Germany (not available in the UK for the ST) and I haven't seen another one yet.
Car is standard except for Eibach lowering springs, 7x16 RS wheels (16" wheels were standard over here, 17" option) and a panasonic ICE.

(at Bridge of Oich, Caledonian Canal, May 2010)