At 200 yards ammo section isn't very important... PMC will do excellent
The 50 is an inhearantly accurate round, I wouldn't worry about match ammo at all until you go past 1000 yards (heck even then bulk ammo is fine)
I'd be thinking more about what optics to use lol
I'd assume the bare minimum would be a 8x. I'd personally probably go with a 12x or something