White Plastic Sleeves For Roca D2D?

Can anyone help please. I need the two white plastic sleeves that fit inside the D2d Dual Push Button. These push down onto the pads within the Valve and flush the toilet.
I have been told i need to buy the whole thing ie the whole D2D Dual Push Button which runs in at approx £19.
I would imagine the two sleeves would be a fraction of this so can anyone supply the above maybe from an old cistern etc?