Duplexer DPF4-4U will be quite effective in case your frequency plan assumes 10 MHz separation between receiving and transmission frequency, the number of channels is rather small, and they occupy not more than 1 MHz band. Channel bandwidth will rise up to 1.5 MHz after installation of six cavities; gain slope will be improved also.
Typical duplexers response curves
DPF4-4U

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DPF4-6U

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