Water pump leak. 1993 400e m119 engine

[umpqua101]

My 1993 400e has a leaking water pump. The Mercedes dealer quoted $1,843 to replace the pump, one hose and the belt. This sounds way out of wack. They say 800 for parts and 900 for labor. The rest is tax.

My second question is; how long will a leaking water pump survive? Or will it self destruct in a short time. Right now I drive about 24 miles without overheating, park for 8 hours and then fill the reservoir with half a quart of water. Repeat. This has been for the last week.