You can get a sky online? Oh my. So many questions.
Can you get other parts of pictures? Can I get a rose bush or a flock of birds?
Are there vendors who take otherwise damaged pictures and strip them for parts? Photo wrecking yards? "This one's garbage, but look at that cow. Anybody could use that cow."
Who's the main customer for these? I bet it's art directors. I've always been suspicious of art directors. This doesn't help.
Has anybody built a photo kit? Like a jigsaw puzzle or an adult coloring book? Box of components -- sky, mountains, meadow, stream. Make it your own by adding optional elements -- fence, cow, flock of birds. Put it all together and you get a beautiful landscape, suitable for framing. Ages 6-adult. Kickstarter?