I take Jarrows Inositol powder for anxiety and OC issues.
My daughter does too.
I used to take it regularly once I had tested it out in the beginning, but now I use it as an emergency measure as mrsD alerted me to potential for a certain amount of tolerance.

1/4 teaspoon = 600 mg

quoting info on the one I buy from iHerb

iHerb Health Library - Inositol Info

Now if I need to leave the house and go into the big scary world I take a 1/2 to a full teaspoon. Depending on how I'm feeling. If I start to feel a little off or over speedy during the day, I take it then too.

Neither of us, feel any GI side effects.

I received a sample bottle of PharmaGABA when I ordered last time, but I've not tried that yet.
Vits and Supps are very expensive in Au., so I buy them from the US and they are passed by customs just fine.

[Also a note about SAMe. It raises mood nicely but tends to also raise anxiety after a while for me, so I stay away from that.]

I still haven't bought the L-Theanine, but I want to try that. Just so many $ can be spent.