The Chalk River reactor is shutdown and use to be the worlds largest supplier. You cant use a power reactor, it has to be a relatively high power research reactor with some very specific design attributes. These are typically 40+ year old reactors. There is a reactor in Belgium as well as one in South Africa that have take up the slack. This material does end up as priority cargo on commercial airlines all over the world and frequently going across boarders. Canada is focused on developing a linear accelerator alternatives.