Yes that's correct, the 300 wsm won't fit in the single stack magazine. I see they do this one now that takes the regular AICS double stack magazines. We would definitely have to get one in here to model for the inlet but it can be done.
Winchester Model 70 Wide Mouth (SA) or FN Police SPR Stealth Detachable Mag Bottom Metal at Pacific Tool and Gauge
pacifictoolandgauge.com
Regarding CDI, Jeff was a great friend to us and we still have some of the DBMS. We've been saving them in case we ever wanted to produce them again. I haven't seen anyone else come out with anything like CDI since he passed.