right now the only LED thats 90+ CRI and neutral tint is the nichia 119, and those are hard to come by.
hmm.. oveready was selling peak eigers with that LED. if you find one, you can use the eiger with 2xAAA body also.
if you are able to get your hands on those LEDs, you would have to do some mod work, or find someone to do it for you.
Interesting. Yes well I'm looking for at least a CRI of 92 and 5000-5500k. The closer to 5500k the better though. At least we are moving into territory where these emitters are becoming available.Most currently available High CRI emitters have tints considerably warmer than 5500K (like 3000-4000K).
McGizmo makes the only light I have seen with CRI and CCT near your stated parameters. The light engine for most SunDrop McGizmos use a Nichia 083B and I think the binning was for CRI 96 and CCT 5600-5800K (and it is interesting that the XR-U bezel seemed to increase the CCT in that range).
One of his later threads mentions that the highest CCT tint bin for the newer Nichia 119 emitters was (at the time of posting) about 4500K and CRI 92.