The bibliography below is neither representative nor exhaustive. It's not exactly random either, but it is not fully fleshed out. It is somewhat organized by geography, but that shouldn't lead you to think geography influences rhetoric: power influences rhetoric.
Traditional Greek rhetoric presumed the delicate fiction of a flat social hierarchy, a deliberative situation where the successes and the failures of the state were shared equally by all (or at least all of those that mattered). If an argument lead to a wrong conclusion, the ship of state foundered and all hands were lost. Therefore, clever, manipulative, "rhetorical" techniques like those exemplified by Polus and Calicles in Plato's Gorgias should be shunned, while transparent, direct, logos-centric arguments should be presented without guile and varnished by craft.
While disagreements among equal citizens still happen, more often the people involved in a disaggreement have unequal status and will gain or lose disprportionally depending on what decisions are made. Often the participants with the least social status have the most to lose and the least capacity or right to participate directly in the decision making. Thus they employ rhetorical techniques designed to influence invisibly. They hide their motives, ingratiate themselves, flatter, condone failures and overpraise successes, seek clandestine relationships, coconspirators, courses of action that twist and turn and meander in ways that maximize opportunities for success and minimize risk by seeming vague or unfocused or formless.
You should say and so nothing. Tallk about everything, but say nothing. Make an appearance of being very active, but do nothing. You should never take a defnite positioin, becuase it may turn out to be wrong or might offend some powerful person. Six Ways to Obtain an Official Position, Lee Zhong Wu. In the appendix of Thick Face, Black Heart.
The weak, in other words, must emplou any subterfuge that might get them what they want without directly asking for it or otherwise seeming to assert their own will. As Han-Fei said, "Undertakings succeed through secrecy but fail through being found out." (The Difficulties of Persuaision)
The books linked here vary in many ways, and some are much better than others for various reasons, in my opinion, but with one exception they all openly discuss rhetorical techniques that would make a Greek rhetor blush.
The Wisdom of Psychopaths isn't a rhetorical handbook per se, but it has an interesting discussion of "cold empathy" that clearly connects to Machiavelli and Thick Face, Black Heart.
The Prince, Niccoḷ Machiavelli
The Art of Worldly Wisdom, Baltasar Gracián
The Wisdom of Psychopaths, Kevin Dutton
The Craft of Power , R.G.H. Siu
Thick Face, Black Heart , Chin-Ning Chu
Intrigues of the Warring States, J. I. Crump
The Seven Military Classics of Ancient China (The Six Secret Teachings) , Ralph D. Sawyer
Han-Fei: Basic Writings , Han-Fei
A Treatise on Efficacy: Between Western and Chinese Thinking , Francois Jullien
The 48 Rules of Power, Robert Greene
The Art of Money Getting , P. T. Barnum
How to Win Friends and Influence People , Dale Carnegie
, Edward BernaysThe Hidden Persuaders , Vance Packard
All Marketers are Liars , Seth Godin
The Charisma Myth: How Anyone can Master the Art of Personal Magnetism, Olivia Fox Cabane
Fascinate: Your Seven Triggers to Persuasion, Sally Hogshead
Get the Life You Want: Secrets to Quick and Lasting Life Change with Neuro-Linguistic Programming , Richard Bandler
Brainwash: The Secret History of Mind Control , Dominic Streatfeild