Amazon, eBay or your local pharmacy. Check how this nootropic is regulated in your country (it could be over-the-counter, prescription-based, or even banned — though this is very rare for herbal extracts). It’s over the counter in the US and Australia.
If it helps a friend of mine had slightly enhanced dreams without any other effects. If you find that it adversely affects your mood, just stop taking it :) (It’s a reversible inhibitor.)