Does FaceTime work if I purchase my iPhone in Saudi Arabia then move countries?
This blog-post claims, selecting a different country in the settings while setting up your account already does the trick. But since the article is from 2010, it may not apply to iOS8:
http://www.macgasm.net/2010/10/23/facetime-saudi-arabia-workaround/

YouTube video about iOS 8 and Facetime, based on a jailbroken device using Cydia:
https://www.youtube.com/watch?v=_6QSRN3NUec

It's a shame Apple bends down to those regimes and prunes down key functionality. Clearly shows that iMessage / Facetime encryption works (as long as you trust Apple).

You might want to look into Signal (encrypted audio calls, Instant messaging should be coming in first half of 2015):
https://itunes.apple.com/app/signal-private-messenger/id874139669?mt=8

Hope this helps!