Maps for U.S. Garmin 810?

May 1, 2014
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#1
Aloha, all.
I'm looking for a source for good maps of Japan that are compatible with US Garmin products.
If anyone has experience with the Garmin "world" map let me know. It seems to be the only mapping provided by (US)Garmin for Japan.
Any other solutions/experiences such as Japanese maps working in a US 810 are welcome.