How much will it cost to repair timing belt approximately ?

The T belt will run around $500. The only issue is why did it break. If you need a water pump or tensioner it will be a couple hundred more. Keep in mind I am from NH and the labor rate is $90 per hour. This engine in not known to last long. I would take a look at the car as a whole and make a decision from that. It is only worth around 1000-1300.