What power adapter do I need for A1475 iPad Air 2013 64gb model

it would minimum be a 10Watt one

output 5volts (all ios chargers does)

have a connector that fits the cable

and that is pretty much the only requirements

The iPad Air1 was originally supplied in its box with a 12W Power Adapter - and requires a minimum of 10W to reliably (albeit slowly) charge.

Whilst your iPad supports optimum/maximum charging from a 12W USB Power Adapter (2.4A @5V), you can use a higher wattage Power Adapter without worry. The iPad will only draw the power that it requires.