Is there a landing place at the lighthouse. If so, what tide can you land, high/low? Is it just a case of looking for a good weather window or is the rest of the year out?
Not sure about landing place, though there must be something. Fraztiree will probably know.
Does this ariel photo help at all? http://canmore.rcahms.gov.uk/en/site...e+lighthouse/# its obviously not recent - and I would guess that the NLB are not maintaining the "shore" access as they will fly in when required?