Sure. A Winchester group will have W.R.A. on the housing. The hammer will be marked WRA on the side, not on top like all other brands. The safety has a different shape than SA. The trigger guard will be marked WRA. The trigger won't have anything stamped on it except maybe a tiny letter A. The odds of having all those correct parts are pretty slim. All this stuff can be looked up with some detective work.
A -12 SA trigger housing should have a -3 or -5 hammer. The trigger guard is forged, not stamped. Early safeties are C46008 -6 or -9.
I think that's about it.