Leaking Coolant

My Espace Mk3 2.2 DCi is constantly leaking coolant from the Timing case water pump cover as highlighted in the attached picture. Its a slow drip when stationary but speeds up as the engine warms up to a steady flow at full temperature. Ive checked the oil and it doesnt appear to be mixing with the coolant so dont think its a leaking head gasket.
Temperate works find and the gauge reads normal until the coolant runs low then rises as expected. Im getting about 20 miles before I have to fill the header tank again.

Im guessing the water pump but looking for some guidance. Is it an easy repair and what sort of cost. Im on a tight budget and rely on the car for work and family.

Thanks

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Leaking Coolant