Selectors wishing to go on purchasing trips to Iran must have an up-to-date knowledge of the economic sanctions imposed on that country. I refrain from giving advice in this area as rules and regulations change from time to time. Please contact me personally if you wish to know more about the particular challenges my library faced when I went on a purchasing trip to Tehran.
Many of the economic sanctions imposed on Iran were recently lifted as a result of the agreement signed between Iran and the P5+1 countries. See the US Department of Treasury's announcement.
For Canadian sanctions, see this Global Affairs Canada page.