Seems the Jubilee is a much more simple build. The sound travels on the same plane throughout the process instead of two planes. (sound comes out and bends around to the front whereas, if I recall correctly with the Khorn, the sound first goes UP, then changes direction to sideways and then comes out)
I didn't know you weren't 'domestic'. No, they don't use the same parts.... the Jubilee uses the 12" K31 driver (actually it uses a pair of them per cabinet) unlike the Khorn which uses a single K33, 15" driver.
One of the design goals for the bass bin is/was to raise the crossover point so it could be taken back to a 2-way.
You could always use the LaScala top end until you got the chance to buy a pair of K510's or (the best choice) the K402.
The "JubeScala" is the large K02 horn atop the LaScala bass bin.... if the stock LaScala will make you happy, the K402 on top will still drop your jaw to the floor.
That said, there are certainly some realities you have to deal with... if you could find a Klipsch Cinema dealer somewhere, you might have better access than you think. (then again, I don't really know).
Was just trying to throw some ideas out for you while you are in the investigation stage.