Some people still believe the name "Sea King" was given to this aircraft by Westland. It was not. The Sea King was named Sea King by Sikorsky.
Boeing would go on to name their next naval helicopter (a year after the introduction of the Sea King) the Sea Knight/CH-46.
What was the Agusta version?
The Sea King - built by Agusta, see
here. It was used to fly the Pope until the introduction of the AW139.
Designation Agusta-Sikorsky SH-3D