My @ cents, people from Argentina, and companies, use US residents as their "mules" to buy things in the USA. Getting stuff like HiFi gear is extremely, and I mean extremely expensive because the import tariffs.
I forget what the tariffs are but they are something like x2 x3 the invoicing. A few years ago, I travelled for business to BsAs 4-5 times, and when I was asked what I like to do and mentioned my HiFi hobby and showed some pictures of my setups this couple jumped off the table. They were all over it. To make the story short, I ended buying a TT, an amp and yes speakers that a "mule" got through customs for me!
I am not saying this person is legit, but what this person is proposing is a common way for them to get things into the country. I also have a similar story with a Brazilian gentleman.
Think of Argentina and Brazil as a modern East Germany in the 70s-80s, their governments are nothing short of Russian style governments. For example, people were dying, still are, and both governments made illegal to import COVID vaccines from the EU, Japan, and USA. They either got a Chinese or Russian vaccines, almost a year after everyone was getting vaccinated.
Just my 2 cents, but people in Argentina have been nothing short kind and hard workers and they make the best they can with the little they have.
Cross your Ts, dot your Is and see if this person is legit. I just don’t dismiss people from other cultures and regions because they do things differently than me.