Portable Lights ( single and double ) don't show up on the Empty Objects .
Objects :
Land_PortableLight_single_F
Land_PortableLight_double_F
Note:
Though you can't find these objects on when trying to place them , I found them on the ArmA 3 Campaign missions where you can copy them to your missions , though if you try ( for example ) change the elevation the object will change to timber ( which is in the same categorie of the portable lights : Construction )