Gasax - there are no sloping ground landing limits for the Sea King - only for shutting down the rotor on a slope. However, as you rightly surmise there will be a physical limit to how much of a slope you can land on and in the Sea King it is the droop stops. If you are carrying out a sloping ground landing and you have to use so much in-slope cyclic that the rotors are prevented from further flapping by the droop stops (droop stop pounding) then it is time to take the hint and find a better landing area. With a nose up slope on our Sea Kings, the proximity of the Sand Filter assembly is a major factor and landing on slopes of more than 5 degrees should be done with great care.
You will be pleased to know that if we can't land on to rescue you then we will winch our very friendly and highly trained winchman down to you to patch you up/put you in a stretcher before winching you to safety.