Installation instructions:
Unzip the archive to Steam\steamapps\common\OVERKILL's The Walking Dead\OTWD\Content\Paks\~mods
If you don't have the ~mods directory, create one.

Here's a cool cheat mod for you. I quadrupled all suppressors' durability.
I picked the number 4 because you'll be playing this 4-player coop game solo anyway.

For reference, it's enough to go through 56 shots on the AWP and still have roughly half of the suppressor durability bar left.