copyrighted music for player piano?

Looking for more modern high quality files for a QRS player piano system. New to this, but it seems like midi files are the most likely to find since specialty qrs / player piano file formats seem nearly nonexistent on the internet. Having a hard time finding copyrighted more modern (most available internet midi files for piano are from 1800s) song libraries of decent quality. Can anyone here point me in the right direction?