At the end of this episode, the famous "See you, Space Cowboy" line is said by Andy.
The "Cowboy Bebop" commercial break image for episode 22, "Cowboy Funk", is designed to resemble the logo from the movie Flash Gordon (1980).
Miyamoto Musashi was one of Japan's most famous samurai warriors.
Maybe be a reference or unintentional by the writers, to Ted Kaczynski the Unabomber, he made bombs and send them through the mail. There is also the similarity in having the Teddy Bomber mailing his "manifesto" to Punch and Judy.
The surname for "Andy von de Oniyate" is probably a reference to Juan de Oñate, a controversial governor of Santa Fe Nuevo Mexico during Spanish colonial times, since "niya" would probably be the closest Japanese rendering of pronunciation of the enye ("ñ") in this surname. Adding the German language "von" particle (to indicate nobility) to this obviously Spanish surname simply adds to the absurdity of this character.