You want a map from the period or would you be okay with some modern maps showing the routes? If it is the latter, here I leave you the whole docent plan of professor Jesús Varela Marcos, my mentor. One of the folders is called "SeminarioDerrotas" and contains what he teaches about the secret trade routes of the 18th century. There is also a beautiful powerpoint about the history of cartography and the Spanish geographic explorations.

https://drive.google.com/folderview?id=1n27i2xcYr8zs0Szl4FWgE7Xuyc7tiuXG