Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
Not that cheap Trig, I bought a set of 8, with the rubber seals for £6.45 inc post from Thailand (they were listed for C50/70/90) and arrived in about 10 days, seem to be very good quality for pattern parts.
I'll dig it out for you tomorrow Trig, need to be on my PC to find it!
Cheap >> http://www.ebay.co.uk/itm/CB550-K-1974-78-Tappet-Cover-New-/140948070141