Hopefully you have found your answer by now but if not...
I'm using V4L Vapor King
batteries, they are Kr808d copies and should work with most Kr8 compatible equipment.
GotVapes has a version of their FLuXomizer for the 808's. It's a horizontal coil with a wick but no packing (batting, polyfil, etc.). I believe it's what called a CE2.
They work great on my V4L batteries. Superior to the vertical coil cartos, IMO.
I'm having problems with most of them having an off flavor when new but I have one that has no bad flavor and I've been using it exclusively for 23 days (about 30 refills, for me.) and it's great. Minimal leakage, good flavor, good vapor. I'm going to try cleaning the new ones with PGA before filling them to see if that will help. I tried a dry burn on one of them, it made the bad flavor worse. The leakage is at the mouth end but only when in use, similar to the leakage at the mouth end of a vertical coil carto.