sorry, don´t know.
(I believe not much, because the price is high.)
But, maybe in bad days, it´s a good idea to get it uncomplicated in comparison with other ways, or get it safer.
I think, if nobody knows that, you must buy it and evaporate the solvent(s), if you are interested in it.
You researched hard on this site or others?
And for da price, it´s maybe relative, but again, don´t know.
mindlib
Edit: And if you do that, I´m sure, you will contribute a little...,right?