Old PM on rural island, one of ours far from London? (15)

I believe the answer is:

northcountryman

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'one of ours far from london?' is the definition.
I can't tell whether this defines the answer.

'old pm on rural island' is the wordplay.
'old pm' becomes 'north' (Lord North, c8th-century prime minister).
'on' means one lot of letters go next to another.
'rural' becomes 'country' (similar in meaning).
'island' becomes 'Man' (the Isle of Man is an example).
'north'+'country'+'man'='NORTHCOUNTRYMAN'

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I've seen this clue in The Times.

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