I just picked up a 450 bushmaster upper and a 50 Beowulf upper and was looking at the mags the Beowulf look just like gi mags with a little lip mod. fallower looks like gi could std gi be ground a little to work? the bushmaster is the same with a different follower can you buy followers and mod gi mags? the 6.8 spc I am out of luck with need to buy 6.8 mags. I have about 60 gi mags