A sign in the town of Salvation says "Kubert's Barber Shop". Joe Kubert was an iconic artist for DC Comics best known for his work on Hawkman among others.
It is revealed that Rip named his son Jonas in honor of Jonah Hex.
The title "The Magnificent Eight" is a play on title of the iconic The Magnificent Seven (1960) film.
This is the second live-action appearance of Jonah Hex after the film Jonah Hex (2010) starring Josh Brolin in the title role.