Come to think of it, that might be the set that I have. Egads, what if I am using the 000 and still getting a loose guage?! I need to find that box...
ETA: I found them! Actually, I think I am a doofus... I believe I am using size 1s from the set which means I can still go down in size.
Next socks I can try the 2x2 ribbing
OMG! I just found a site that goes down to 0000-0000! I wonder if that's still in US sizes... http://www.purseparadise.com/knittingneedles.html