Hi, Stooby,
I don't know why your post is locked from replies but, any hard-wood is fine for Intarsia type projects, projects like book-ends, cell phone holders, card holders, etc and most of the scrollers
seem to prefer Baltic Birch plywood for fretwork projects.
I do not recommend any particular on-line seller but, you can research prices by looking for
Baltic Birch plywood.
God Bless! Spirithorse