I have a narrow band capable Kenwood tkr750 for sale. I can program and tune the front end to your frequency pair. I'm asking 600.00 plus shipping from 69361. It's heavy and large so figure about 100.00 on packing/ shipping / insurance.
I will also consider (preferred over sale) a Motorola T1500 Series UHF 440-470 split 4 or 6 Cavity Pass / Reject Duplexer (or cellwave / wacom equivalent) in straight trade ( again preferred over outright cash sale).