Sorry for the confusion. I'm not familiar with the area you were asking about. When you mentioned San Juan, I immediately thought of Puerto Rico.
The chart list for the SD card TZT-CHT-SD1 are located here:
http://www.furunousa.com/ProductDocumen ... 204-14.pdf
The coverage for the SDUS01VS57MAP11 and SDUS05RMAP08 include only US waters. This is because NOAA (a US organization funded by US taxpayers) is only allowed to survey US waters and the data is available for no additional cost. The Canadian version of NOAA isn't funded by their taxpayers and therefore charts for that country (and most other countries) are "for fee" only.
The easiest way to see a "view" of that coverage area is to go to the mapmedia website (
http://www.mapmedia.com/charts-catalog.html) and select "Vector", "Mega Wide & NOAA" and "NOAA" to show the vector chart info. To show the raster coverage area, from the same website, choose "Raster", "Mega Wide & NOAA" and "NOAA".
Any areas that include Canadian waters would need to be purchased. The missing notch of coverage that you may note in the two charts you mentioned are included in the SDVJNAM025MAP06 (Furuno USA part number: MM3-VNA-025). That coverage area can be viewed by going to the mapmedia website (above) and typing "025" in the box below the world map graphic and choosing the version ending in "6.1".
I hope this clears up any misunderstanding.