Thanks Eric, I ended up using their links to the SRTMGL? pages
#. SRTMGL3 tiles: [https://lpdaac.usgs.gov/products/srtmgl3v003].
#. SRTMGL1 tiles: [https://lpdaac.usgs.gov/products/srtmgl1v003].
since I am not sure if the NASADEM files differ - will have to check a few. Also, the nasadem does not mention 3s.