I can help you configure compatible antennas for the MX67c.  Since the connector is RPSMAFemale, which means it has a threaded body and a solid copper pin.  You will need a jumper cable between the Radio and the antenna or a connector adapter.  Also, you may need to extend the antenna to a place where the antenna near an outdoor window , door, etc. so you have line of site.  If the radio and antenna are behind a wall that is cinderblock or a wall with reflective material, the signal will not get out:
MFG Part Number: M3070090D20607  Has two N-style connectors.  You will also need two cable to conncect it to RPSMAFemale on the radio.
MFG Part Number: 195-06-20-P5'  5 Foot extension cable to connect the antenna to the radio