As the part of AONE5, we fly from Sao Paulo to Buenos Aires by BA and then transfer to domestic airport(Aeroparque Jorge Newbery) for Iguazu by LAN Argentina.
The JAL agent did not know how far those airports are, so she booked us with 3 hours connecting time.

The system allowed the connecting flight with 3 hours connecting time.
Is this enough time considering immigration and pick up luggage and clear the custom, and then take taxi or shuttle to domestic airport around noon time?

What is the best way for transfer between those two airports, by Taxi or any airline shuttle?

Thanks in advance