Hi! You can find one at uruguaiana street, it is the place where you can buy most of things very cheap.
Thanks, do you have any idea how much do I have to pay?
Uruguaiana is a huge electronics (and everything else) street market in downtown Rio (metro stop Uruguaiana) where you will find dozens of dealers selling what you want. Competition is fierce which keeps prices reasonable. Don't be afraid to bargain!
You can also go to LOJAS AMERICANAS - there is one in every square in everu mall. i bought mine, with waranty, for 70 reais, duo chip, radio, ZTN is the brand