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Funny you use the word brand, as that is a generic, unbranded cart. Probably work fine.
This style is available all over the place. For a generic, but branded, one, check out comapnies like Seattle Sports. The top of the line is Wheeleez, with little niceties like anodizing after the holes are drilled (those that don't are more likely to corrode at the holes at some point).
That said, I have moved away from pneumatic tires, as the ones I had lost air over time and I never had a pump around to pump it up. Tire sidewalls finally gave out due to too low pressure. I put Wheeleez Tuff ties on my generic cart.
Expect the straps that attach it to your boat to not be great (most of the ones I have seen are pretty crappy), but that is easily fixed by using the same sort of straps you'd attach a boat to the car with.
This one is easy to build.