Replacement needed for a MasterPiece/MP sliding patio-door dual-hook mortise lock

Replacement needed for a MasterPiece/MP sliding patio-door dual-hook mortise lock.  Faceplate is 6 1/8 × ¾ inch; mounting holes approximately 4 5/8 –4¾ inches center-to-center; lock body approximately 3 1/8 × 1 1/8 × ½ inch; actuator approximately ¼ inch square with 7/8 -inch backset. Internal spring is loose/broken.