Jon, Quentin are telling you correctly and they know about the ARs. Also you should be able to pick up a good quality forged Lower for around $100.(*Not Cast! Because there are some of them out there!) Be sure and ask about the Lower before you purchase it. Also just to give you some info. Good quality Lowers are *Forged and they are made of 7075 T-6 Aluminum.
And you still would only have $770.00 in a good AR since you have a good upper assembly. You could always trade or sell the Polymer Lower you have.
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