What is the average cost of replacing a timing chain tensioner and water pump Mechanic wants 2400 They said pump replacement is recommended?

Timing Chain Tensioner for a 92 Nissan Maxima is roughly 100$-140$ and water pump around 100$ NAPA Auto parts prices

Timing Chain Tensioner for a 92 Nissan maxima is roughly 100$-140$ and water pump around 100$ NAPA Auto parts prices