restore default firewall config for esxi 5.5

While trying to add a new firewall rule file I accidentally copied my new XML over the top of the primary /etc/vmware/firewall/service.xml config file. I'm booting our free ESXI 5.5 server from a USB flash drive. I'm not sure whether the modified service.xml file will persist through a reboot but if it does the firewall settings will be missing all the default entries. Is there a way to retrieve that file from a config backup, the USB flash drive or perhaps an online repository? I've looked at our state.tgz backup files and they do not appear to contain the service.xml file.