You can order a copy of the MASH reunion show here

Check out this page to buy a copy of a homemade DVD for the reunion show, now selling for $15 plus $5 shipping and handling:

http://www.ioffer.com/i/M-A-S-H-30TH-ANNIVERSARY-REUNION-DVD-COMPLETE- UNCUT-23833102

If the page is no longer available, try doing a search on that site for the title of the show.

Also, TVLand network reruns it periodically. It was playing tonight.