In any given category of necks in the Showcase, look at Vintage or Vintage Modern, and then do a filter on any given lumber type (or if you feel like scrolling through a lot of results, "All exotics"), and you'll find out what already exists in the shop. A quick look at just Strat necks gave me flame maple (roasted and un-treated), rosewood, bocote, padauk, canary, goncalo alves, and pau ferro under Strat necks. There might also be Brazilian ebony but the filter doesn't have that as a choice; but I'm pretty certain I've seen them in the past. Some of the necks I saw in my results at may be two-piece parts, but many are quite evidently one-piece jobs.