I used a Vesrah Kit, from D Silver, I think, which had everything, including seals, O rings and rubber pucks that I needed, however on the strong advice of the sages on this board I used a genuine Honda head gasket, which was visibly much higher quality, with a 'sticky'coating, and you don't want to take the engine out again if it fails.
Mine came from CMS, I'm afraid the price will make your eyes water, though, over £100 with VAT and carriage.