Carlos this place is tremendous to go to practice in the Range but a tip, the magazines you can buy them here in Academy sport they have one in Orlando and Kissimee in this place you can get them cheaper but I don't know if they have the one you are looking for. I checked you out and they have a 12 rd one for $ 44.99. I don't know how much it'll be worth in the Oak Ridge gun range
Yes, in America you can get whatever you want legally. Please don't illegally modify your weapon.
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