Hi Again Don, Stu is correct, depending on the circumstances. In the field, I believe you would pick up what is available, matching or not, proper or not. Depending on when the magazine was lost, broken, etc. a plastic botton could be substituted, by an armorer.
I think you have to come up with a scenario you are trying to achieve, then look for that magazine.
Sounds to me that whatever you have, might be good enough!!
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