One barrel is about 254l (V = π * h * ( D²/2 + d²/4 ) / 3) - jack Daniels barrel is 90x60. The wort of the barrel is 319€ (see jack Daniels store).
So... 8.600-319€ = 8.281/ 254l =32,60€/l.
Jack Daniels cost around 26€/l (depends on store)
FOLLOW 4 LUGH