I got the blocks off Ebay, though I can't find the link now. The one below is just a similar one. None of them seem to list for 2021 or 22 but I found that the ones for a 2020 fit fine. I didn't get the kit with u-bolts because I don't much trust Chinese steel. (The blocks would be hard to fail). I went to a spring shop and they custom made the u-bolts for $55.
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