You may also be able to find a suitable replacement with a current driver. It would mean a little bit if backengineering and for the sake of consistency, you'd want to change both drivers. It can be done; you'll just have to do some serious reading. Find the Theil/small parameters of the original driver: either write B&W or since one driver is working, start measuring it. Then search the net for a comparable (and most likely superior) new model. You'll also have to know the crossover point and type, in addition to the cabinet volume, tuning (if bass reflex), etc. It may entail some changes to the crossover: not alignment changes or parts upgrades, but, I believe, just because the new driver may be different in a few parameter you'll have to change a few component values in the crossover. That's all I know off hand, but I don't know that specific speaker. If B&W has the information I can't see any reason for them not wanting to give it to you since the speaker is out of production and they're not going to lose any money. Sometimes though the companies are lazy and just don't care though, or even keep records.