Might be a silly question......but have you called Paiste and asked them?
They might have a spare one on a shelf somewhere, as drum companies often make more than one if someone before has special ordered something. Its worth a try.
Otherwise track down Jeff Ockletree. He makes Paiste Drums and was a drum tech for John Bonham, Danny Carey, Billy Cobham etc. He knows everything about Paiste and Id imagin he'd have a few spare ones he might be willing to part with. Hope this helps.