I have been collecting Jack Daniels decanters and antique bottles for 15 years or more now and I have never seen anything quite like yours. I have a library of over 1500 pictures of every bottle and jug made from the late 18oo's to the current releases as well and still nothing like yours.
It is similar in design to the Riverboat Captain decanter released in 1987 but not really.
I don't think I wouldn't sell it at all if it were in my collection.!!!
I have seen this picture somewhere else recently and remember several of the comments made about it being a fake. I really don't think so.
In my opinion, it's the real deal and is probably one very valuable piece. I know of a man, who has a full and sealed paper label bottle from around the early 1900's that is valued at $10,000.There are still several of these types of bottles around ..
I have an opinion as to what it is worth, but it is just my opinion. It's really worth what ever someone is willing to pay for it.
Thanks for showing it ..
southrock