Your engine could have a 4 or 6 cylinder engine, 6 cylinder is more expensive to reseal. You are probably being quoted for new timing belt,cam seals, crank cseal, tension and oil pump seal. On the 4 cylinder the oil pump is driven by the timing belt and I have seen the oil pump seal and oil pump shaft seal leak. I have also on higher mileage cars seen the oil pump shaft its self wear. I could see replacing all the parts getting up to $700 with labor.
Thanks for your response - its a 4 cylinder engine. I don;t think they are replacing anything as i enquired, its only cleaning the timing cover and resealing it, toping off the engine oil. the high quote is there as they say its labor intensive - i got it from 4.5 hrs to 7 hrs ranging from $700 pretax to $370 pretax for this so i am confused.