This is intriguing. If it is okay, may I ask a few questions first.
Are these actual Jubilees from Klipsch or are they clones (do they have Klipsch stickers on them)?
What was the horn on top? (the K-402 is about 41 in wide, or the K-510 is about 15 in wide) or were there two horns (like in the picture posted by DJK?
Or perhaps the tweeter/midrange was a home brew configuration.
How was the crossover implemented (analog or digital etc)?
Enough with all my questions.... Yes, I don't think you should worry about the size of the room. Think of them as a Klipschorn with an enclosed back. The should be placed near corners (preferably) but they do not need to be tight into the corners.
It is very difficult to guess at an appropriate price. A new pair (bass bin and HF horn/driver) is roughly the same price as a new Klipschorn. But they would not have grills, crossovers, HF cabinet, and little or no cosmetic details. The used prices are only a wild guess since so few of these come up for sale. The figure mentioned previously ($1500) is probably a fluke that we can only dream of. If they are a "clone" then it is even more difficult to even hazard a guess.