250-500cc custom wr300 wheel build help req

My old factory excel rims and hub need a tidy up and whilst there I would like to change the colour of the spoke nipples to anodized blue.
Im looking for info about where I can get these from. Has anyone ordered these parts online, if so could you help with part details ?
Looking to end up with something like this aftr I powdercoat the hubs pearl blue




Cheers
S