C, importing into the US regardless of what part of the world you are coming from and what good you are going to bring in will require both continued presence in there during license application, sound business advisors and depending on how big your investments are, you might think of getting legal advise, even just in the beginning. Insurance, Health, Agriculture, Food and Drug Admi. these are just a few of the departments that you will need either one or all of them to set up a business in USA. Oh, BTW do you have a business license in there already? You will also need an importer's license to bring your products in. Leather is not an easy thing to get a license for, USDA was not very helpful on that application - that had been tried. Textiles - just like anything in US, they have to meet trade quotas and lately Asia is their best of pals in this department.
USA after the 9/11 have changed documentation and background checking for allowing shipment (large or small) to get into US ports. I should know coz for 10 years I was dealing with incoming parts (for manufacturing products) to enter the US for production purposes. And after the 9/11 background checks even of our international suppliers were checked, funding sources (against money laundering connections and terrorist connections are to be my company's obligation - for to be caught with a slight link to either guns, drug or worst terrorist connection to money - they can seize all your assets, just like that- Homeland Security has really have their eyes everywhere, as they should) bank transfers and what countries do you get your raw materials from, and on and on...
Importing in the US, will involve loads of paperwork. Brokers, freight company and their cost are exorbitant, now that the US is at war - there is fuel surcharge and war tax . These little fees do add up and fast.
It is not that easy to get an import license in the US, it is doable but you need help to get it under one year.I know of someone who bought another person's import license to avoid all this hassle, but that too is risky. Allowing another person to use your name, and if something goes wrong, though unintentional can cause you tons of headache.
The easy part is exporting out of Argentina will be easy, since you obviously speak the language and know people here but preparing to get your cargo into the USA will another ball of wax.
The best thing that Argentina has ever exported to the US are the brilliant minds that help them with the world of science and math in there, and that only takes an HB1 visa.