Far as I know (and I could be wrong) both versions can use either mags. But if you had your heart set on Pmags, you can buy them in 3-packs from Airsoft Global, $170. Works out to $56 each, but you're gonna pay hefty in shipping...
http://www.airsoftglobal.com/shop/in...ducts_id=15592
I'm tempted to try and start collecting pmags, because when the KWA Masada comes out, regular stanag mags are gonna look wierd in it :-)