Activating old DCS games on my Steam account

[GD Mast]

Hello,

 

After a long time away from this forum and playing flight sim games, I would like to know if it's still possible to activate my games on STEAM. I've got DCS World activated on my STEAM account but would like to know if I can activate A-10C Warthog, DCS: Blackshark, Lock-On and Lock-On: Flaming Cliffs (all boxed versions). I know these are old but still gold. Any help would be greatly appreciated.

 

GD Mast