The Amazing 3 (partially found English dub of anime series; 1965)
The Amazing 3 (Wonder 3 or W3 in Japan) is a 1965 manga series created by legendary manga writer Osamu Tezuka. It focuses on a trio of aliens disguised as a duck, horse, and a rabbit. An anime adaptation of the manga started airing on Japanese and American television in 1965. While the Japanese version of the anime can still be found on the Internet, the American dub is very hard to find and is rumoured to be destroyed. The last time the English dub of the anime was ever aired and seen on American Television was during the 1970s on Kcop-TV as reruns. A few episodes of the English dub were uploaded to YouTube sometime in 2013 or 2014 but later got removed most likely due to copyright infringement.
YouTube user Peter Vasiliou uploaded 2 and 1/2 episodes in English (not the best quality) he says he will try uploading more when he has time.