Well you can do this with an argentine bank account, but not with the debit card, you have to do it with the credit card, is the same, but you have a limit per month, around 1500 usd a common argentine credit card you may or may not firts call visa customer service to enable this option, you can even talk with your bank to raise your limit for 1 month asking a credit and giving it back in the first day of the next month to avoid been charged by interest, some people i know had done that, and some others not sure how were getting dollars throught turistic agencies here in Argentina, other people go to casinos in Uruguay buy 1000 usd with the Argentine credit card, drink a coke or what ever in the casino and then change the casino coins to dollars, there are other ways but that are the most common ones to get dollars at oficial rate with your argentine bank account and credit card.