Where to exchange dollars for Euros?

You can try Wise (formerly TransferWise). Wise exchange rates are generally good. You can change USD to EURO with Wise, and then transfer Euro to wherever you want.

If you want to do Euro to ARS (Peso), you can use Western Union.

It seems WU doesn't accept Wise virtual account numbers. However, you can open a bank account remotely in Portugal (Novobanco). E-residence can help get Portuguese Tax ID (NIF) and open bank account remotely.

Then, transfer Euros from Novobanco to WU, WU to ARS.

There is no transaction fee from Wise to Novobanco (or Novobanco to Wise).

However, Novobanco charges about 8 bucks per month to maintain a bank account.
E-residence also has some fees to open bank account/NIF. However, if you are earning Euros, then it's worth giving a shot.
Thanks for all the replies. I was contacted by a board member and was able to get the Euros I needed.
Anyone looking to buy Euros tomorrow? An Italian friend arrives tomorrow and needs to buy pesos.