It sounds like Bitcoins would have to be taken into the country physically and exchanged by trading.
The person taking in the BTC would end up with a load of Pesos though, which probably isn't what they would want. It sounds difficult to arrange getting Bitcoins into an already closed system.
About 10 days ago, a local BTC exchange site was created, which allows to trade ARS/BTC (Unisend.com). Before this, the only way to obtain BTC was through localbitcoins or OTC, but you always ended up paying more than the actual value of a BTC in USD...