I have tried eBay and other disc sources. I haven't found all the pieces in one collection. I did purchase a CD from the Northwest Chamber Orchestra that had four of them on the same disc - the most so far.
But I like the Acman3 idea - I have a CD recorder that allows me to record off of my streaming service (or whatever). I bet I can create my own CD (or two) of the full series by piecing together the various one-offs I have found off of Qobuz.
For now, that will be my solution. Thank you both for helping...
David