In Spain the Papyre 6.2 are sold for US$ 350.-
If you take into account taxes, transportation, commision fees, etc., I don't think US$ 100 more are that much.
Besides, in
http://www.garbarino.com/informatica/e-readers you can buy it in 18 installments with no interest, as long as you have a Santander Rio credit card.
In
http://www.mercadolibre.com.ar you can get the Sony and Papyre, in several installments too, with or without interest, depending on your credit card's bank.
The advantege of buying in Argentina is that you have warranty in the country.
The big problem is the ex-change rate: 1 US$ = 4 ar$
