Thank you for the answers.
JBC Catalog 2008 (for previous generation of compact stations "Singles") says that they are not compatible.
http://www.howardelectronics.com/jbc/images/Catalog%20JBC%2008.pdf
Are you looking at a new one or used?
Either way, I wouldn't expect anything to be listed as compatible with the CF models due to the stand portion is incompatible with any other iron, even though it's the same control circuits.
But if you're willing to modify, could be made to work (it should be relatively easy actually; there's a wire that connects the metal part of the stand that contacts the iron to the PCB; circuit is completed when the iron is inserted to activate setback/sleep features). Separate/modular units use a connector to accomplish this. Take a look for teardown pics and videos and you'll see what I'm talking about. Manuals of the modular line would help slightly as well (shows the connector and wire between the base and stand).
Modern catalogs and manuals doesn't say anything.
CD-BD manual (.pdf). This is the current model, and can use the T210, T245, or T470 series irons, which can be found on pages 10 & 11.
(can't even imagine why they are so expencive)
They all are at this price point unfortunately.
Combination of relatively small production, what/how they're made (then hit with a nice markup). For example, imagine cast aluminum parts that require assembly with other bits on a small scale, likely being primarily hand operations (not as likely to be heavily automated like the casting & assembly operations for automobile engines).
Cheaper ones may actually be plastic/rubber or just stamped metal. As a result, they tend not to weigh as much, and aren't as stable.