As explained on the parent website, LS/LF breakfast cereal options in US mainstream stores are limited: Post Shredded Wheat: Regular and Spoon Size, Quaker Oats Life, Weetabix, and many - but not all - Kashi cereals.
Here is another option that has some distribution in mainstream stores. Perky's Crunchy Rice, formerly called "Nutty Rice" even though it did not contain any nuts, is a crunchy cereal that really is LS/LF. Note the sodium is 110 mg/serving, not the maximum allowed 140 for products labeled low sodium. If it matters to you, it turns out that it has no gluten.
It is a crunchy granular cereal somewhat like Grape-nuts, but with less than half the sodium of Grape-nuts. I like to mix it in with LS/LF granola since it has a nice crunch which does not fade after (no fat) milk is added.
Why can't mainstream manufacturers make more foods like this?