Hi David
I think you can order the copper washer at Z-power.
http://www.z-power.co.uk/z900a4-kz900b1 ... 0010001100The rubber damper could become a problem.
The parts numbers are: 92075192, 92075193 and 92075194.
Keep in mind that the rubber damper is available in 3 different measurements. The thickness is marked on the damper with stars (very little ones, use a magnifing glass to see them) There are 1, 2 or 3 stars. These represent the thickness, one star for the thinnest, three stars for the thickest.
If you have the old damper figure out which one you need. If not, install the rotor with the starter cluth and measure the gap to know which one you need for your engine.
Good luck
Philippe