Look at Ebay. Some 14-day doses asking $600. There are also Russian sellers with raw bulk potassium iodide for sale. Looks like a powder. I suppose so people can compound their own pills? IIRC, people need to be careful handling the raw chemical as it is an irritant.
There are also side effects to ingestion of potassium iodide and some people cannot tolerate it. Why are folks taking it so early? You are right; this is just hysteria.