This is a bit of a different idea and rather quirky.
London based vintage emporium, Colporter, collect and frame vintage old opera scores. The scores are all intact, with the sheet music preserved inside the frame. A selection of opera scores are available, with covers ranging in colour from blue, to turquoise and green. You can pick which score you’d like and whether you’d prefer a black or white frame.
I really like the idea (especially as the score is preserved and hasn’t just had the cover taken off, as is often the case when other similar old materials are framed) and it would make a special home gift for fans of opera.