I appreciate your spirit here, David, but I think it's all directed to the wrong places. Given the option of A) saving your money to afford a used pair of R-10s which pop up on here at least a few times a year or B) trying to rally general support to get Sony to make a newer, better, cheaper thing -- you chose the latter.
You have readily admitted that you have never actually heard the R10s, so I think your first point of action is clear. Save up some cash, or attend a major meet, and see if the currently available offerings can't do what you want.
Please also keep in mind a few points:
1) Headphones are just transducers. The music capable of being reproduced on a pair of R10s today is far better than it was when thy were first introduced. Better sources and better amplification make for a better listening experience.
2) New stuff won't be cheaper. The only circumstance whereby even a limited run could be profitable is by using old parts and selling for exorbitant prices. In all likelihood, the limited run would cost as much or more than the used offerings currently available, and would not sound any better.
3) We are by no means a big enough market to justify a dedicated run. There are maybe 20 R10s owned by active members of this forum, and those are constantly circulating. I heard the pair owned by Ray Samuels, and I doubt he's ever selling. If we were, as a community, buying hundreds of Stax 007s, Ultrasone Ed. 9s and Grado GS1000s things would be different. Right now I can't justify spending over 1000$ on a pair of headphones, and I doubt you can either. We are all in debt to those individuals on this forum who have devoted countless hours of their lives to being in a position where they could reasonably procure these headphones and wite about them with authority. They are, however, few and far between. If the enthusiasts can't do it, how are we to expect the general, disinterested populace to do it?
4) I don't know if you realize how good things are right now. Th fact that there was EVER an r10 is a miracle, but there are currently available production headphones that rival even the king in quality. Go and listen to them. Decide for yourself if what you need is yet another higher, unobtainable tier.
5) More mass-market headphones are good for us. More low-level headphones help global economies of scale, and make it more likely that a company can afford to produce a flagship product, and that consumers will have the capacity and the inclination to buy it. Apple sells HD650s on its website right now, and that's spectacular. Even more spectacular is that the comments page on those headphones instructs purchasers that they need an amp to drive them properly, and that they can find more information at, you guessed it, head-fi.org.
Times are good, man. The fact that "the king" is no longer in production is inevitable. The unobtainable will always be the most desirable. I think you should take your passion away from manufacturers, and turn it towards the community. Go out and listen to some of these products, and sorry about your wallet.