Hi Tom, Greg, Richard, et al.,
This is the cover to the "Kentucky Battle Song" songsheet, published in 1864. While the flags shown were perhaps based on the facts of the units' services, I do not believe any were based on actual flags. However, this does appear to be the source for the t-shirts and various repro flags that one sees now and again at reenactments, &c.
You can see the "Kentucky Battle Song" sheet cover at http://www.rootsweb.com/~orphanhm/flags.htm (bottom of the page).
Geoff