Thats what we do:
Teacher accounts only, and I mark everything in our library that is already in "Makemusic Cloud." Everyone in here will agree that once it went cloud based, it went downhill in many ways. I used to be able to record accompaniment with the clicks and email them to students to practice, and that doesnt even work anymore.
I know you may not have the time, but easy solos that are not in there, I will input them into notation (I use Flat) and export them as audio files. I may even do this with some harder solos if it's worth my time.
There have been a few class ones that I have asked our choir teacher to record for me. She plays them on her digital keyboard as midi files and can mess with tempo a little bit. That's not the greatest option, but its okay.
I don't do this, but I know some people will find accompaniment videos on a certain website that plays videos, and they will use other websites to take that certain video and strip the audio from it and then save the audio file. I am sure you could search that if you need more info.