Possible Clues:

• Buyer
• 'One is after the end of this and by it, by the sound of him (9)'
• One who buys tea consumed by officer on board ship
• Patron has ship's officer storing tea
• Chief steward bringing in tea for a customer
• Shopper put tea in bag, right?
• One expecting to be charged
• Ship's officer stores tea he's bought
• Customer wanting neat short, and another drink to follow
• I'll buy short, neat whisky after beer perhaps