Downlodable files for certain user levels from the backend

Hello everyone. I have a Multisite installation with a few blogs in it, and I’ve been trying to find a way to let the super admin upload files (in this case pdf’s) from the backend which will be downloadble for certain user levels, in the backend. Let’s say all users with the role Administrator from all the sub blogs will see these pdfs somehow while logged in to the backend and be able to download them.

I’ve done some research but only come up with plugins that will let me manage files in post and pages.

Maybe there is no plugin for this in which case I can build one myself, but I’m pretty new to the whole WordPress scene so I wouldn’t know what data is available for me from the WP core.

The idea is to create a plugin that will show a menu in the backend only if you’re an Administrator and fetch all the .pdf-files from the Media Library, how does this sound? Is there a better way?

Thanks in advance