Build a Nuke for $150 million

The anonymous commenter in the story below made me curious. The comment refers to this news item. The seller apparently had graduated from selling dime bags of pot to harder items. "This stuff is really the bomb" he alledgedly said.

Doing the math - $150 million to buy enough weapons grade uranium for a bomb. Not affordable on an NIH grant. But perhaps within the reach of a state-sponsored terrorist group.