Just as a response to some vehicles/equipment they could add for the Syrians, PT-76, MT-LB, D-30's used for direct fire, Ural trucks, ZSU-24-4 used in direct fire role, various AA mounts such as the ZSU-4 and OT-64's, BTR-70A, BTR-40, BTR-150, BTR-50's
Assuming Syria has kept some of their older tank stocks, give insurgents or conscripts a T-34-85 with a few rounds of HE ammunition or even better SU-100 or IS-3's!