Incidentally, after much searching I located a scan of the completed art!
Here is a hastily colored version:
Also, here is an unfinished and unpublished cover to issue #12. The published version features a much more extreme close-up of Magneto and Sauron.
Here are a series of sketches made in preparation for the series:
And finally, although not unpublished, this alternate cover to issue two is not easy to find:
For more Hidden Years art, and art by John Byrne, check out: