No, that is an aftermarket add on unit that you could get at like a NAPA or car store.
As far as factory, my understanding was that Speed control was a 73 mid-year option and if you ordered it, it was (as Chrysler has doone in the past) sent in the trunk and dealer installed. However it was a factory unit as you can see in my pics. Wasn't on the build sheet either I'm told.
74 was the first year Chargers came from the factory with it installed and the washer reservoir was different as well, again see photos of my car
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