KDOG, I have all 3 of my "12P"s sitting in front of me. Let me see what I can tell you.
1. 12P- This one is a 9P plus an extender I got from Lighthound, not a SF A19. I currently have a Z32 bezel on it. The Z32s are black level 2 annodised, are cusioned for shock and are generally used on shotguns. They only cost about $24. This 12P has an old 12V Digilight lamp assembly in it. They are out of business. You could buy and use G&Ps current 12V LA. I have one. The beams on these are about 10% brighter than a P91 and have good throw and great spill. They put out the same amount of light as my Digilight. The Digilight is a little more "SureFire perfect" or smooth. In my experience the level 2 annodising holds up well. This one fits great in coat pockets or even front pants pockets.
2. 12P with Cabelas 1.7 inch Turbo Head. This is also built on a 9P plus an extender. The colors match up great. It is about 240 lumens and the beam hot spot is somewhere between the Z44 bezel, with a 12V LA, and an M4 Turbo Head. Not bad for $30 plus shipping. There is no lamp available, so if it burns out you buy another head. SF P91 LAs are close to $30. This one fits great in my soft briefcase.
3. I used my Leef 4 battery, black annodised, body to put a SF KT2 black Turbo head on, with the appropriate SF bulb. The colors match up great. SF leggo is fun! Now I have an M4 for the back door.
I guess you could get an HA Leef 4 battery body with a SF HA tailcap and a Z44 HA bezel. That should all match up. SF makes HA KT2 turbo heads also, for any future leggo games. Your problem with an HA C3 body is only being able to get black extenders, as far as I know. I am also not a fan of putting extenders on combat ringed bodies. They look funny. But I will admit I did it for a while with my Z3. It then became a Z4.
I hope all this helps.