Your range will be asnothers have said, after 200 miles you should fill it. Testing the limits will always work to your disadvantage, that long uphill climb fully loaded won't factor into thinking and the Norge does not like to be pushed.
At a steady cruise in the 4500-5000 rpm range you can get some amazing MPG figures and think something isn't right until the next leg reveals the same.
A brand new Norge with top case but last model year shouldn't go for much more than the high 11s and the usual tax/license OTD. It might be possible to find a late model 8 valve for 5 and 1/2 but that might take some doing.