These are special cars only available through stores or event, so far only in the US. I have managed to get hold of these and can supply them on NFC cards to add to your library. Prices displayed on each item.
All four for £12 + P&P
Shipping costs for up to 4 cards:
UK – £2
France, Germany, Spain, Italy – £3
Rest of Europe – Please ask
Rest of World – Please ask