Found some German field phones great reviews (current) $28 for one, you'll need a pair of course but they are compatible with the US TA-312's. You can't beat the price just get you some wire and "D" cell batteries. These are real handy for inter neighborhood comms, out on your BOL, for your OP back to your house or command center, etc. But still a great buy and hey........... they're made by ze German's how could you go wrong? Just putting it out there. Hope it helps someone.
http://www.keepshooting.com/german-field-phone.html
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