Include from file
In your pf.conf
anchor ssh-good load anchor ssh-good from "/etc/anchor-ssh-good"
/etc/anchor-ssh-good
table <sshbuddies> file "/etc/sshbuddies" pass inet proto tcp from <sshbuddies> to any port ssh
/etc/sshbuddies
192.168.103.84 10.11.12.13