This site states this directly: SodaPeak has no authorized retail or marketplace channel we could find. Direct-only distribution is what keeps the 60-day guarantee enforceable.
Any listing found elsewhere — a marketplace, a third-party retailer — would sit outside the official 60-day guarantee, per this site's own materials, worth understanding before buying from any source other than the official checkout.
Order only through the official SodaPeak checkout, and be skeptical of any third-party listing claiming to sell the same product with the same guarantee.