My Box Set Solution

I would make the case that this is another example of type 1 - collection of albums. They may not have been previously released, so not having existing, unique album art. But, they will likely have a sub-title.

I looked at the example you gave and each of the 80 CDs does have a unique album jacket (looking at the Amazon product photos). Looking at the upper right corner, you can see printing to the left of the disc number, so that seems like a sub-title.