I called tokico a couple of weeks ago, and unfortunetly the blues for the B12 are no longer available from them. The B13 Blues (Charles describes how to install B13 struts on a B12 in the article with the AGXs) are still available, but at that point you might as well get AGXs or Koni (the Koni are inserts are the B12, which I think are the same as the B13 but I'm not sure, are still available).
I was going to buy them, good thing I called before I ordered them. I hear the Konis are better anyways.
EDIT:
As far as springs go, you can get the Eibach sportline or prokit, Sprint, Suspension Techniques as well (IIRC). Please stay away from the eBay stuff, and I've never really heard anything positive about ST or Sprint, performance-wise. B13 springs fit as well, so you can get B+G springs for a B13, which is what I ordered

. From what I hear, B+G tend to be stiffer than Eibach in general (I don't know exact spring rates for our application though), and B+G are less expensive than Eibach as well.
Tien is also developing springs for the B13, but I have not seen a ship date for those, they are listed in the 2005 catalog though. I'll keep an out and post when I find out (I love working at an aftermarket distributor sometimes

).