If you are interested in doing some hard work and are able to do something technically you can go over to the Garmin Mobile PC section of this forum and find something.
There is a program called Mapsource by Garmin that can be installed and used to view Garmin-compatible maps that you can get at places like
malsingmaps.com. Some are free, some are not.
Mapsource does not do navigation but lets you load maps onto your PC and view them. There is another Garmin program called "nroute" that will navigate using maps that you have loaded in Mapsource.
nroute is a free download and all you need to have is Mapsource installed.
There is a way you can legally install Mapsource from Garmin but it is not simple to do if you are not technical. If you are interested, there is a discussion how to do it in the
Garmin Mobile PC section on this forum. There is also information at Malsingmaps how to use Garmin-compatible maps with your GPS. There are many maps at Malsingmaps and other places that are free for south-east Asia.
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