$ pkg list -n entire
to show the latest version available *from configured publishers*. Both pkg search and pkg list examine configured publishers.
So what does
$ pkg publisher solaris
show? Are you looking only at a local package repository? If so, is that repository up-to-date?
To show the latest available SRU, look at the support repository, or look at MOS doc Oracle Solaris 11.3 Support Repository Updates (SRU) Index (Doc ID 2045311.1)