You make a lot of it. The costume looks authentic. Detailed, good colour-scheme, and you're the fitting type, also nice hair. Your photographer mastered to catch the MGS1 atmosphere via the colour-contrasts, which indeed makes a major strength of it. But you still got to replace the custom M14 with a PSG-1. Great job overall, keep it up.
As for the gun, this was all I could find for the last minute debut, the real thing is in the works!