1997 Other Fiat Models Fiat Punto 1997, engin size 1.1

Engine Cooling problem
1997 Other Fiat Models Front Wheel Drive Manual 70,000 miles

Dear sir,

I have a Fiat Punto, 1997, S60 SX, 70000 mileage. Within 10 minutes of driving, the temperature of its engine will go beyond the meters and its engine give s metallic "tatata tatata." Sounds.

The garage told me that it must be the header gasket problem and get it fixed for me. However, they claim the problem was not fixed, saying the coolant leakage might be the root cause and if I don't fix it, in the near future, the engine will burn the header gasket again. To fix the coolant leakage, they have to replace the core tag inside the engine. They said the component will cost 1 pound but the labour is very expensive. And they didn't give me a definite answer whether it'll be fixed or not.

What would you think the root cause might be? What would you think if it's worthy of fixing?

Thanks a lot!