Cheap source for new front disc wave washers?

Has anyone found a source for replacing the wave washers used with the front disc spacers? (to suit '08 GSA Spoked wheels)
Im aware of the per side kits available from moto-bins but I would imagine the wave washers are the only part likely to need replacing when doing a new set of front discs and they should be an off the shelf part for pennies as opposed to £30 a side for the complete kit.
Found this supplier but was wondering if anyone had already bought some to solve this problem previously?
Failing that anyone ever measure one up when looking for a replacement?

TBH at that price it's worth the risk. Buy them and measure against the ones you take off the bike. Cheap washers will be plated steel so expect corrosion. Who knows if the BMW versions are stainless.

Just looked on the parts catalouge,

Cant see wavy washers, just floating disks.

can you be more model specific?

Mart