There is a lovely big repository of free maps from the University of Texas.
We can access them through google earth: upload the index layer and then click the centre of a map square and it will open.
Is there a way to have all this as part of Sasplanet ?
The maps are here: https://maps.lib.utexas.edu/maps/topo/index.html
and this man has a video on how to access them here: https://www.youtube.com/watch?v=_9i-UrK6Oio