You could search for an archived mirror of ftp.netscape.com. Like for example https://ftp.nluug.nl/netscape/communicator/english/4.77/unix/unsupported/sunos54/n

You could search for an archived mirror of ftp.netscape.com. Like for example https://ftp.nluug.nl/netscape/communicator/english/4.77/unix/unsupported/sunos54/navigator_standalone/ https://ftp.nluug.nl/netscape/communicator/english/4.77/unix...