Hi Jeremy,
Following Richards train of thought....
From LXNav FlarmMouse Manual - LXNav FlarmMouse - 36 mA at 12 Volts, plus an extra 10mA at 12 Volts if using the standard LXNav external LED display.
From LX Navigation Red Box Manual - LX Navigation Red Box - ca. 60 mA at 12 volts, plus extra if using e.g. an LX Navigation external LED display. (LX Navigation recommends a 1 Amp fuse in the Red Box power lead at 12 volts, so presumably supply should be rated at least 1 Amp.)
I'm sure others will have plenty of alternative suggestions. Fortunately I'm on a 12 volt system (with a Charge 4).
Regards
Peter