Euro straight male porn stars Cage, Neeo, and Martin Gun have all done quite a few gay scenes early in their careers. If you look at their Rame profiles, the titles highlighted in blue are their gay films.
http://www.iafd.com/person.rme/perfid=neeo/gender=m/neeo.htm
http://www.iafd.com/person.rme/perfid=cage_m_eu/gender=m/cage.htm
http://www.iafd.com/person.rme/perfid=martingun/gender=m/martin-gun.htm
And don't forget their close friend Leny Ewil!