I'm confused about your confusion. It's pretty much a standard that any brake rotor has minimum allowed wear specification stamped somewhere on a non-wearing surface. (The manual also says to look for the specs stamped on the rotor.)
Why wouldn't the specs be stamped on the rear rotor?
Trying to determine if the thing is worn beyond taking them to a shop to have them turned.
My confusion is that you didn't originally ask for a minimum thickness specification.
Since your vehicle is a 2006 Police Charger, I assume the rotors have been replaced at least once (maybe more) and aftermarket rotors don't always have the stamp you are looking for (particularly if they are Police Duty rotors, they use book specs). Some have the nominal new thickness number stamped (for a percent/nominal measurement reduction calculation) and some have none stamped at all. They may also not be the same specs as OEM depending on what they are.
Many brake shops will simply measure the thickness and use book numbers to determine the ability to further turn the rotors.
What are your thickness measurements of the total rotor as well as the inner and outer plates (assuming they are vented)?