@bttfbrasilfan
Was Brasilian dubbing from original VHS, or TV recording?
The first time Star Wars aired on BR television was by 81-83. This audio source I got after a couple months of research around the web. Someone from "Forum Dublanet" sent me .wav files by email. So, I can't tell you exactly where they came from (TV or VHS). But be sure that there are only two dubbings: the one made before the SE and the one made for the SE.
Oh, last year I found an Star Wars VHS sold on mercadolivre.com (similar to ebay) that had "Dublado" (Dubbed) printed on the front cover.
Well, I think we have another one for sale. But this time with Empire price$. Anyway, it's good to check the cover.
http://produto.mercadolivre.com.br/MLB-509794081-guerra-nas-estrelas-star-wars-dublado-vhs-_JM