Many sellers are willing to send "samples" - the listing usually states a minimum quantity, which is typically 1 kg. That's how I got CD-3 from Alibaba - three whole kilograms. There was an issue, though, with the fact that I don't have a registered company, in principle they don't sell to end consumers, but in my case they agreed. I was telling them I was "in the process of opening a company", and they were telling me they "believed" me and that there wouldn't be a problem. In the end, I'm happy with the final result of this little "affair"