Look for a local wood turners supplier. They usually stock various timber blanks. Some saw mills deal in exotics and hard woods as well.
I have a few hundred quids worth of timber blanks in my shed for wood turning although I havent done any for years now. Cant decide whether to keep the lathe or sell it.
Strangest thing I turned was a grass root blank or maybe a banksia nut, you get furry tools and lathe with that one. Fun though.