Quentin Tarantino has always been famous or infamous for ripping off scenes from various movies. Cowboys & Indians had pointed to this first and The Hateful Eight definitely borrows from the episode Fair Game of the TV show The Rebel which was aired in 1960. There are way too many similarities like the whole thing taking place at a stagecoach station, a bounty hunter with a female prisoner, a poisoning incident and then everyone under suspicion, the prisoner offering a deal and so on. Even some of the lines are similar. Check out the episode Fair Game of TV show The Rebel.
Synopsis of the episode Fair Game of TV show The Rebel
Yuma meets Pace at a stage depot. They are soon joined by passengers on an arriving stage to wait overnight for a stage connection. Among the passengers on the arriving stage are bounty hunter Farnum with his prisoner Cynthia Kenyon who is wanted for murder. When Farnum is poisoned, the others want to release Kenyon to prevent harm to themselves but Yuma prevents it.