rendered output

    salt_mirror:
      file.managed:
        - name: /srv/salt/mirror_us.conf
        - source: salt://saltstack/files/myfile.conf.j2
        - template: jinja
        - user: root
        - group: root
        - mode: 0600
        - master: ftp.us.debian.org
        - master: ftp.debian.org
        - master: ftp.debian.org

    salt_mirror:
      file.managed:
        - name: /srv/salt/mirror_uk.conf
        - source: salt://saltstack/files/myfile.conf.j2
        - template: jinja
        - user: root
        - group: root
        - mode: 0600
        - master: ftp.debian.org
        - master: ftp.uk.debian.org
        - master: ftp.debian.org

    salt_mirror:
      file.managed:
        - name: /srv/salt/mirror_ua.conf
        - source: salt://saltstack/files/myfile.conf.j2
        - template: jinja
        - user: root
        - group: root
        - mode: 0600
        - master: ftp.debian.org
        - master: ftp.debian.org
        - master: ftp.ua.debian.org

state.test.sls

{% for location in salt.pillar.get('salt:locations') %}
salt_mirror:
  file.managed:
    - name: /srv/salt/mirror_{{ location }}.conf
    - source: salt://saltstack/files/myfile.conf.j2
    - template: jinja
    - user: root
    - group: root
    - mode: 0600
  {%- for mirror in salt.pillar.get('salt:mirrors') %}
    {%- if location in mirror %}
    - master: {{ mirror }}
    {%- else %}
    - master: ftp.debian.org
    {%- endif %}
  {%- endfor %}
{% endfor %}