I'm a fan of these sorts of brands, too. I'd guess these products are hard to find because they don't show the same year after year growth you'd see with heavily marketed brands. Not the kind of returns a VC firm is going to want, anyway.
You need a stable brand, stable products, and patient owners.
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You might be interested in N0-AD suncare, which does only sunscreen. I've https://no-ad.com/