At long last, you can stream Aeterna in full. Find the player embedded at page bottom, or take in with its natural surroundings at Bandcamp. Best with “headphone use and without equalization. Uninterrupted listening at highest (but tolerable) volume is kindly advised.”
From the look of it, there are still some CD copies available. The Swan has also alluded to a forthcoming vinyl edition as a double LP set.