Hi cariredjeki,
Are you after any specific brands? Technically these have "brand names" and they offer different types of swimwear -
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If you are referring to designer brand clothing such as Ralph Lauren or Hilfiger for example, the only option of getting them aside from their authorized distributors would be from liquidators. However with liquidation they come in pallet mixed with other brands. And the availability is not constant. Liquidators get closeouts and salvage items directly from some of the top department stores, so they frequently have some top designer brands in their inventory.
Hope this helps. :)