In Resident Evil 5, Chris has two costumes that are unlockable for the primary story mode.
Chris’ Safari Outfit – To unlock this outfit, simply beat every misson on any difficulty.
Chris’ S.T.A.R.S. Outfit – To unlock this outfit you have to beat every mission on any difficulty, and collect at least 25 BSAA emblems during story mode.
Once this criteria is met, you should see them as purchasable for 0 points in the Bonus Features section. Once they are purchased, you will be able to select them in the Special Settings section.