Well, by reference to the BBC's Gilligan, his source 'existed' -- the source (Kelly) was not a "spokesman" for the agency/gov't, he was a critic of the gov't, acting alone and under the cover of press secrecy.
So is that the case with this "CIA Official"? I assume yes, since he is not a spokesman for the agency or for the Bush administration.
Does the Bush administration have enemies in the CIA? Of course they do -- this source could be, i.e., Ambassador Wilson's wife (Valerie Plume) for all you know.
Here's the cite:
http://www.freerepublic.com/focus/news/browse?ao=1
The story opens by saying:
Philadelphia Inquirer ^ | 11-12-03 | Jonathon S. Landay WASHINGTON - A new, top-secret CIA report from Iraq warns that growing numbers of Iraqis are concluding the U.S.-led coalition can be defeated and are supporting the insurgents. The report paints a bleak picture of the political and security situation in Iraq and cautions that the U.S.-led drive to rebuild the country as a democracy could collapse unless corrective actions are taken immediately.
Now, how do you think that the Phil Enquirer received a "top-secret report"? Maybe from an unnamed "CIA Official" hostile to the Bush administration?