I am going to start building the gun pictured, featured in the videogames Metal Gear Solid 3 and Metal Gear Solid 4. I just had a question about some of the parts on the gun, and they may be just something designed by the creators for the game. Is there any similar style trigger out there like the one pictured, with 4 holes? And has anyone ever seen a mainspring housing like the one pictured? If not, does anyone know a place I could have these parts fabricated? I would appreciate anyone that can steer me in the right direction. Thanks in advance!