Q: Are water pump repairable, ie change the bearing and seal

Hello - no, the water pump cannot be repaired by a mechanic or technician. The rebuilders and remanufacturers (sometimes the original manufacturers of the part) have access to parts and tooling not available to pretty-much everyone else. Quite often, the manufacturers require your old pump as a "core" so they can rebuild it. I would recommend having a Water Pump Replacement Service completed by a mobile, professional mechanic, such as one from YourMechanic, to diagnose this problem, get an accurate assessment of damage and cost estimate for repairs.