The package freight companies in my experience are completely incompetent when it comes to handling high technology imports. I have never seen one come up with an accurate HTS number for an import. That in turn means you almost always end up paying more in duties than you should. Often you can put a product into more than one HTS entry. I always advise picking the one with the lowest duty. Customs can always argue the point, but as long as your position isn't unreasonable, there is no penalty involved.
Light Emitting Diodes are Harmonized Tariff Schedule (HTS) 8541.40.2000,
and unless there has been a case brought before the International Trade Commission for dumping, the tariff is probably 20% for imports from the PRC, from most of the rest of the world the import duty is ZERO.
That only covers Light emitting diodes themselves, not LED flashlights or anything else.
(Flashlights are 35% duty, 8513.90.2000, from the PRC).
My suggestion would be to have the goods air freighted instead of shipped UPS or Fedex, and let a local customs broker handle it for you. Just tell him the value, the number of LED's, and remind him that it should be 8541.40.2000 if all you are importing is LED's.
In the case of mounted LED's, you can probably claim that the value of the mounting is minimal, and consequently doesn't impact the HTS classification.