I do not know if there is any offline alternative... But maybe there is one out there.
Weapons to unlock are as follows:
Sniper: M95 (heavy Sniper rifle, more damage)
Special Forces: G36C (short version of the G36 automatic rifle, very good accuracy, more damage)
Assault: G3 (the G3 automatic rifle, no grenade launcher, more damage)
Support: PKM (heavy support weapon, slower rate of fire, more damage)
Medic: L85A1 (slight zoom, more damage, about the same accuracy)
Engineer: Jackhammer mk3A1 (great at close-range combat)
Anti-Tank: DAO-12 (like the jackhammer great at close-range combat)
I have so far unlocked the PKM and the L85A1, I have also tested all but the Jackhammer... Will soon get my 3rd unlock.
