You can demand them now, the NSN was in Kit Magazine two issues ago IIRC.
I have a bright Yellow one in my Bergan. Mainly because I bought it for civvie use.
To answer the inevitable question "but it's not tactical" (you know the liner that inside your DPM bergan, that you wouldn't go into if it wasn't safe to do so) I reply. Ahhhh, but when I need to bring a heli in, I pull it out of my bergan, and voila instant bergan sized heli marker. With no extra weight.
Funny thing is, some of our "warriors" are now purchasing Red and Yellow canoe bags for this very purpose!!!!