This issue is a variant of Marvel Masterworks: The X-Men (Marvel, 2003 series) #4 [Regular Edition].
Reprints X-Men (Marvel, 1963 Series) #32-42. Volume 35 in the Marvel Masterworks Library.
This is most of the cover from The X-Men (Marvel, 1963 Series) #36.
Artist's reconstruction of the Comics Code rejected, "Outcast" X-Men cover.