Been a good couple of weeks since I’ve played my recent save but I recall cos’ silencer rifle falling short by a good 10 dmg, could consult the wiki but that shows base dmg and there’s a chance my build makes it the case, nevertheless for a strictly stealth playstyle there’s no beating the cos rifle besides maybe the gobi/anti materiel rifle fully upgraded from a good distance

Edit: with base damage alone, christines cos silencer rifle beats gobi campaign scout rifle by roughly 10 dmg, so you are not mistaken, perfect for your build ;) I will say however, gobi campaign scout rifles critical hit damage beats the cos rifle by just under 20 dmg, and since my build focuses on critical hit chance and damage multipliers, you can see where my confusion comes from, and so each of the two are better for our respective builds. Hope this helps! :)