However, that's quite expensive (I know the postage is included).
These three from B&C Express come up a tenner cheaper (although I don't know what postage is). Can't fault Renthal/Tsubaki kit, or the service I've had from B&C in the past...
http://www.bandcexpress.co.uk/chain/...ha-o-ring.html
http://www.bandcexpress.co.uk/sprock...4-jpg-407.html
http://www.bandcexpress.co.uk/sprock...p4-jpg-11.html