Any chance it's a Saiga ak? Or you could adapt to that Magazine type? If so ,they sell 5 rounders.
SGM Tactical Saiga .223 / 5.56 5-Round Polymer Magazine
Perfect for bench shooting or target practice, the SGM Tactical® Saiga® .223/5.56 5-Round Polymer Magazine is the perfect addition to your Saiga rifle. Made from heavy-duty composite polymer, this aftermarket magazine is designed for superior s
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