You dont' really need the HCl (and yes, it's hydrochloric acid).
Orthinine is L-Orthinine. I found it at Whole Foods. I don't know that you NEED it. I took it and it seemed to help me sleep (I am a bit of an insomniac generally). But since that is all it is supposed to help with, I'm sure you can do without.
I did not use the Black-Walnut tincture on my liver flush.