Redirect traffic based on GEO IP lookup (Varnish 4)

GEOIPRedirection.vcl

sub vcl_recv {
  # section.io Edge node automatically performs GEO IP (and city) lookup on every request.
  # We create a request header called "section-io-geo-country" that you can leverage

    if (req.http.section-io-geo-country ~ "^(AU|NZ)$") {
        # Australia and New Zealand
        #return (synth(802, "https://www.domain.com.au/"));
    } else if (req.http.section-io-geo-country ~ "^(US|CA|MX)$") {
        # US, Canada and Mexico
        #return (synth(802, "http://www.domain.com/"));
    } else {
        # UK and the rest of the world
        #return (synth(802, "http://www.domain.co.uk"));
    }
}

sub vcl_synth {
    if (resp.status == 802) {
        set resp.http.Location = resp.reason;
        set resp.status = 302;
        return (deliver);
    }
 }
 
 #Ideas to extend the above:
 #1) Check for a cookie value to override the logic in vcl_recv (and set a cookie value when a user chooses a specific site/country to browse to)
 #2) When redirecting onto a site with GEO IP logic look for a query string such as"redirect=" and 
 #override redirect logic in vcl_recv as this user has been redirected onto the site