2000 Watt Honda Generator
Ukiah Honda
Best price anywhere I could find
$949.00 out the door with a quart of Honda Motor oil
quiet as a mouse
My other backup is a 400 watt Coleman inverter ($24.99) and a spare car battery, this will run my main pump for hours and hours.
(tested it once, got tired of waiting for the battery to wear down)
Nice thing about this is you can swap the battery into a vehicle and charge it back up.
Right now, Costco has 1000 watt inverters for $58.99 or something like that.