If your cooler in the radiator had failed and it put coolant/water into the gearbox - then kiss it goodbye too - the glue that holds the friction material to the clutches in the transmission is water soluble. - They will delaminate and cause severe shuddering and eventual complete failure.
Its quite easy to rebuild the gearbox too provided if you can find a mechanic who
1 has the tooling
2 is willing to do it
and customer is willing to spend the amount - a rebuild kit for it will cost about close to 1200 with a rebuilt torque converter.
I was a mechanic in Pk too - This engine is nothing out of ordinary work, for parts one can get the parts from outside Pakistan or via Indus Motors (they can supply you any toyota part for vehicles they sold in Pakistan. - Ive bought a lot through them too, but 90% of customers now would wince and have heart pains at the pricing of toyota genuine parts)
Disassembly is not costly at all, it takes a grand total of 2 hour to tear down this engine to its pieces and at most 2 hours to remove it from the car itself (if its automatic, 3 or 4 if its manual) - You are probably a customer who shops for a different mechanic anytime your car needs work done. Such leads to perception of expensive labour and lack of workmanship quality.
