Are you sure it's failed? They don't fully fail very often. It could have jammed; you can check by removing the little round cover and turning the slotted axle with a biggish screwdriver. If it really has failed you could easily replace the pump yourself IF whoever installed it put isolator valves each side of it.
Borrow a big wrench, shut off the valves, unscrew the two big unions and remove the pump having first switched off the electricity and disconnected the supply to the pump, noting what wire went where. Take the pump to a retailer and get a replacement. Refitting is the reverse of removal, as they say. You might need to bleed some air out, which is done by unscrewing the little cover on the end.