I bet jk labs could do it, but the price for the cables and box compared to the mics probably wouldn’t be worth it.
I don't have access to my documents now (my main PC literally blew - anyone have a spare Intel P4 478 pins Northwood clocked at 1.8 GHz or better? I though these were surplus and in abundance but apparently not))
From memory:
The MC012 body only has a single center-electrode as far as I remember, so actives running to the body just isn't possible (short of drilling holes in the body. Same problem as with the 480b, SMS2000 and others). But even with holes, the body is still awkward to wire into: it provides a poor interface for actives. So yes, a power unit of some sort is needed.
Wrt failed attemps: If you try to wire passively you loose signal so fast you only get a few inches of useful distance.
Actives:
I am familiar with the mic and it's performance. Not to insult anyone but back when I measured it I wasn't too excited about the capsules. The sample to sample variations were huge as well. So I haven't pursued actives for those capsules (that sounded a little like Mr. Bill Clinton!) But I have amused myself with thinking that technically the -10 dB pads could be transformed into active heads and so allow a lower cost implementation than if machining highly custom parts from scratch.