Numpad *: Unlock SVD Rifle - while in the LOADOUT screen and you can see your sniper rifles, press this key and then use the selector and you will see that the SVD is no unlocked for use, even in early missions.
When I use the option it doesn't give me the SVD but it gives me the Type 99 instead. I don't have any DLC for the game so I'm not sure how I should be getting this rifle
I think the SVD is removed in the latest version, and when the trainer feature is used for the SVD ... it gives you the "last weapon" in the slot - which happens to be the Type-99 shall you not have the DLC. If shall you have the DLC, it gives you an "error code" weapon name ... which will just crash the game shall it be select for a mission.