This really reminds me of this one game called Golden Light with the whole 'weird horror' thing, also reminds me of this other game called 'The Forest' a while back when I played it 4 years ago, and think there's some Fallout 4 vibes in URGE to me as well, I'll check this out sometime.
I put the data below cuz it may be spoiler but idk, its the location of the sniper I found it on the "Rat looking" island between pericolvann and urlando, its on the shack, left side from main entrance second floor inside a closet. It looked very familiar tho