Its the most common of those mods so i'm sure your friend has a bunch but if not you can try to acquire one in Lua spy and with its common nature it might drop relatively easily.
The cool thing is that as long as you are continuously getting headshots the counter resets so you can theoretically have it active for the entire mission. Also its fun if you don't mind trying to get headshots.
my own Journey for Argon scope continues so hopefully DE will unleash the acolytes again.
One of Ivara's parts drops from a Spy Lua right? I need to do that anyway, talk about convenient!
Look up two posts, haha.I have everything I need for the Nikana except argon which I don't even know where to get
Edit: or back, new page oops.