It's not official from Google, but here's a homemade version until they do release it (they seem to lag on the Enterprise version, for some reason).
http://www.twoeighteighty.com/gmaps/gmm_164_bb.zip
It looks like they only include the series versions of GMaps, so the 8800 series will cover the 8800, the 8820, and the 8830. There are individual installations for each of these downloadable from the website, though (see below).
http://www.google.com/gmm/apps/v1.6....20_v4_2_L1.cod
Anyhow, I've separated the 8300 and 8310 by using the GPS="False" and GPS="True" attributes. I'm not sure if there is even a difference between GMaps for the 8300 and 8310, but let's assume there is, for now.
I have tested the ALX load through Application Loader on both the 8300 and 8310 devices, so I can atleast verify it works locally (which should ensure that it'll load wirelessly through a software configuration, as well).