I am not aware of the UK situation but here (Holland) the hosting SC takes care of the NOR and SI. For Nationals and Europeans they need to be submitted for scrutenising, before being published, to the national sailing authority (e.g. RYA).
The NOR and SI for the Europeans have been checked and approved by the Dutch counterpart of RYA. The Europeans NOR is available on the Dutch web-site (http://www.wayfarer.nl/) and the SI I can email if you like (MS-word document).
I would expect the RYA (http://www.rya.org.uk/) to have a standard NOR/SI available on their web-site. If not the Dutch “watersportverbond” (http://www.watersportverbond.nl/) has them available on their web-site (MS-word, in English). You could also check out the ISAF site. There is a lot of usefull stuff there. (http://www.sailing.org/)
Cheers,
Ton