Google Play Edition devices go extinct: the HTC One (M8) GPE is no longer available
Of course, Google might introduce other Play Edition handsets or tablets in the future, though this seems unlikely. A Samsung Galaxy S5 GPE was supposed to be released last year, but that never happened.
Meanwhile, folks in need of a device that runs stock Android can buy themselves a Nexus 9, Nexus 6, or Nexus 5 (with the mention that the Nexus 5 will probably no longer be sold starting the second quarter of the year).
source: Google Play via Droid-life, Android Police
Things that are NOT allowed: