Possible Clues:

• Object added to gallery a very timely gift
• Greatly appreciated gift or opportunity
• Immortal primarily sees death as a blessing
• Manna from heaven!
• Dog's den free — a stroke of good luck
• Blessing ... or, read differently, a theme hint
• Say Pluto's death is an unexpected blessing
• Setter maybe returning with post is a stroke of luck
• Spurs wanting a final point getting a stroke of luck
• Something that arrives just when you need it most