When you go to a Halloween costume store, you'll notice that their Michael Myers masks resemble the design from the later films. The reason for this change was that the Halloween and Halloween 2 masks were modified versions of a William Shatner mask.
Fans and collectors looking for a high-quality replica of the original mask usually sell for hundreds of dollars, but Trick or Treat Studios is developing their own take, which will be available later this year for $59.99:
Via Michael-Myers.net: "It brings me great pleasure to announce that Chris Zephro’s Trick or Treat Studios will be responsible for the OFFICIAL 2012 HalloweeN II Michael Myers mask! The mask is a version of the LUNATIC, sculpted by the talented Justin Mabry. The mask will retail for $59.99 in stores nationwide (and on Trick Or Treat Studios website) and will finally offer HalloweeN fans an accurate, affordable and official Michael Myers mask – something fans have been anticipating for over 30 years. More details and a formal announcement will follow soon."
We'll post more details as they become available, but until then, you can read up on Trick or Treat studios at: http://www.trickortreatstudios.com/