Get at Walmart
You can pick up a copy of this at Walmart for 5 dollars in a compilation called "Martial Arts Masters (Bruce Lee/ Sonny Chiba)", which contains 9 movies (this, fists of fury, and a doc called "The Real Bruce Lee...3 on Chiba (street fighter, return of SF, and Sister SF)...and 3 on nijas (shogun ninja, ninja wars, rage of masters)).
This movie is funny and i must admit i was entertained while watching, although the acting is bad and the dubbing horrid. Just know ahead of time that the movie is not 100 realistic and you'll be a fan too.