None of the tougher sanctions proposed for Iran, says this WSJ front-pager, will target its oil sales, which account for 1/2 of government revenue. The market is so fungible and international and sensitive, that doing so would likely push gas up a $1 here in the States, even though we don't import any Iranian oil--openly.
As a result, no big trick to buy resold Iranian oil, a la the chart above.
"Everyone buys from the Iranians—governments, states, other companies," says Mark Ware, a spokesman for Vitol Group, an energy-trading company that continues to deal in Iranian crude and is one of the few companies willing to talk about it. "It's not subject to any legislation."
This is the reality of a sophisticated global market: all demand affects all production affects all prices.