What brand of liquor does Hancock drink?

In Will Smith's movie "Hancock", he's seen flying with a large bottle of something that's hard to determine. Then later, he's in a store and he brings two bottles to the counter, and there you can clearly see that it's Gentleman Jim's Bourbon. I did a search and could not find any info on Gentleman Jim's Bourbon. Is it real, or is it just a brand that was made up for the movie?