havelock?
What about btcinve.com?
While I haven't heard anything concrete, I don't think Lab_Rat is considering a third-party exchange. BitFunder burned a lot of people pretty badly, and any exchange that gets big enough is going to run the risk of attracting legal attention from the US and having to shut down. I have gotten the impression (which may be incorrect) that Lab_Rat is investigating an "in house" solution that will allow the automated trading of LRM bonds (and only LRM bonds).
grnbrg.