If you are willing to shop on the US side, find the Martini Collectors site with the list of suppliers, and they have a half dozen suppliers links to wood outfits.
Prices vary a lot.
I have been eyballing the Cali'Co Hardwoods blanks. Been told that they require some care setting up on a duplicator, as they are cut fairly close to size, but the offer about the best prices I've seen, the broadest selection of types, too.
Worth a look, IMO.
Cheers
Trev