Ah yes, the Type 79, a Chinese made Submachine gun designed in 1979 and manufactured from 1983, which is technically still being used by some Chinese SWAT Teams with modern modifications.

Gmod version:
https://steamcommunity.com/sharedfiles/filedetails/?id=2753429933

The model was ported from a L4D2 mod with permission granted:
https://steamcommunity.com/sharedfiles/filedetails/?id=2617838300

Includes:
l4d2_mod\zzzs570\type_79\l4d2_mod_type_79.mdl
l4d2_mod\zzzs570\type_79\l4d2_mod_type_79_magazine.mdl

Credits :
zzzs570 - Original creator of the model and the L4D2 mod.
NeoLin - Porting to Gmod and SFM.

Feel free to support the Lambda Group for more addons.👌
https://ko-fi.com/neolin7812
https://www.paypal.com/paypalme/NeoLin7812