I still havent gotten my hands on The Last Bullet. And to be honest, I'm not sure if that's it. I dont see no Garands in that clip you posted.
It might be that it was the series then, as I dont remember the things leading up to the duel, so it might be that I've caught the last episode of it and though it was a movie.
I THINK that towards the end, either the allied or the japanese soldier tried to slit the other's throat with a bayonet but didnt finish the job and so in the reunion part the other had a distinct scar on his throat.