Copes Distributing has them with the Black Teflon Magpul followers. Cache a few so that when yer plastic mags start falling apart you still have extras and can mitigate the lamentations of your brothers who were less wise and failed to stock up before they got banned. These are the good ones.
http://www.copesdistributing.com/ar15-30rd-wmagpul-follower-black-teflon-p-6003.html
http://www.copesdistributing.com/ar15-30rd-wmagpul-follower-black-teflon-p-6003.html