Aqueous Iodine oral solution is BP grade the same as Lugol's 5%. The healthleads Lugol's is a bit weaker and they sell it for £20 for 100ml when you could get it for about £10 for 500ml from a chemist. I know which I'd rather buy.
Yes Hulda Clark s is different, weaker too I think, but the ratio of Iodine to Iodide is the same
That potassium Iodide from iherb is extremely weak so much it needs preservatives . It's no use trying to get any Iodine from the US, it's not worth it. You can't import prescription medicines either.