I have a 276 and love it - everything a big plotter can do , but on batteries for 8 hours ! This place seems to be showing as in stock , but worth a call I reckon.
No idea why they are so hard to get hold of - they are essentially the same as the portable Aviation units - just differing software .
Maybe a call to Garmin themselves would pay off - at least they can see if they are still making them etc, or see if they can point you to a decent dealer who woudl get hold of one for you ?
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