The problem is the EPA in the states. They are so uptight about the fact that they haven't certified them for use in the USA that they have in the past sent threatening correspondence to Canadians who were willing to sell the CDI to interested US citizens. They were actively monitoring the Canadian CsC forum for that at one time.
I know, it sounds paranoid, but it's true. With all the things that the EPA could be worried about, they were getting litigious over one of the most fuel efficient vehicles in North America.
It can be done - but you can't be overt in your inquiries or actions.