To my knowledge, this Ovation Records boxed set was never released on CD, but it seems to be a popular eBay item that doesn't command a huge price. The trick is to find a pristine set. It took me months to find a set of discs that were not free of manufacturing defects, but maybe you will be more lucky than I was.
It's definitely worth having because it contains several items never released elsewhere, plus "suites" of songs direct from soundtracks, so they don't sound like any other issues. The book is nice, too.