This is a good question - Nokia Maps would not indeed seem to be available for the device. I'm guessing it's because it's non-touch Asha device and the screen orientation is different compared to e.g. Asha 303 (which supports Maps). On the other hand Maps is not mentioned on the device page either (http://www.nokia.com/global/products/phone/asha302
Although my Asha 311 has Maps installed it is pretty useless as totally dependent upon network cell tower triangulation so widely inaccurate in rural areas; whereas older S40 devices such as my 3720 Classic allowed you to use additional Bluetooth GPS receiver this is no longer the case with latest S40 devices. There was a policy of removing Nokia Maps from firmware of devices without ability to use "Assisted GPS" and at some point this decision now seems to have been reversed perhaps led by marketing.
Happy to have helped forum with a Support Ratio = 42.5