Chap stowing away boy-king? (5)

I believe the answer is:

lader

'chap stowing away' is the definition.
(person who loads things onto a vessel)

'boy-king?' is the wordplay.
'boy' becomes 'lad' (lad is a kind of boy).
'king?' becomes 'er' (I've seen this in other clues).
'lad'+'er'='LADER'

I've seen this clue in The Independent.

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