Timberline (in SE) does have a stock of old Brazilian rosewood, but it is OLD- ie over 40 years I think and in their words "best used for projects like furniture restoration."
You consider one of the other rosewoods- Sonokelling rosewood is often available plantation-grown these days, much better, although obviously colour not same.
Craft Supplies do get what they call "violet rosewood" in small sizes for turning. Not sure if big enough. Web addresses for both suppliers below.
Welcome To Timberline Craft Supplies - The Home of Wood-turning, Janik, Charles Greville, Sound Wood, ShopSmith ...
Either way, if you use any type of rosewood (ie
Dalbergia species)just remember the dust is very nasty and you'll need extraction plus decent cartridge respirator for hand work.
P.