This needs proper configuration exposed via the management API.

See outbound-socket-binding in the <socket-binding-group> element:

https://github.com/wildfly/wildfly/blob/master/build/src/main/resources/docs/schema/jboss-as-config_2_0.xsd#L1446

The rts config can expose the name of the outbound-socket-binding; this service can inject the SocketBindingService and pull the configuration information from there.