You can bring max $500 of foreign purchases and you'd have to pay 50% duty on the excess of it - so, $750 in your case - provided you come in with an invoice to prove it was paid $2000, otherwise AFIP will assess its value with their own black-box criteria - and provided it is the only foreign purchase you are bringing in since the exemption is not $500 per item, but in total.
Now, you can bring in a used one and you can try to argue it was not purchased abroad and you had it in Argentina, brought it with you abroad, and brought it back. They have no way to verify this and you have no way to prove it either.
In the past you had to declare electronics good you were taking OUT so that you could prove they were already with you in Argentina when you'd come IN. I did this declaration only once (iPhone, reflex camera) and the AFIP office at the airport didn't even had me put my old iPhone 5 and iPad mini 2 because they were of no interest to them.
Also, you can't take OUT more than U$D 2,000 of goods when leaving Argentina. Something I have never heard enforced and found out only recently.