Possible Clues:

• Ship carrying post
• Postal packet going overseas
• 'She sounds like a he on sea (4,4)'
• Sounds as if one might say he sets sail
• Packet accommodating posters overseas?
• Vessel taking lettuce, they say, to and from Kos?
• Sounds as if you couldn't say she sets sail
• By the sound of it, you could not say that she docked in Dun Laoghaire
• Sounds as if he, not she, would set sail