Can you find any mod to play you can it can be Co-op DeathMatch and any others you need is; half life 2, half life 2 EP1, half life 2 EP2, Half life 2 DeathMatch.
This is half life 2 episode 2 source mod based on 1997 epic video game from id software. Note : This demo is in alpha stages so you may expect some bugs but it's worth it. Requirements: Half life 2 Episode 2, 7z Archive manager. Instructions : Open archive and drop the folder 'quake2source' in your Steam\steamapps\sourcemods\