Dear friend I can give you idea about this gear repairing.It is very costly because in rexton engine and gear from mercedese so its parts very expensive.This is better for you first u try to sale it in this condition.As per my knowledge and experience the total cost of gear repairing will be QR.6000/= OR QR.7000/= This is only I am giving you idea,but not confirmed,I know there is one machanic from india,He can help you.If u want to contact this person call me 5235459.
THANKS
ANSARI