Outside of T14, (and even within T14), opportunities to practice "international law" are very limited. This is due to the fact that A) There really isn't such a thing as "international law", and B) Any legal job that has some aspect of internationalism to it, it going to be highly, highly coveted, and thus, highly competitive. Sure, anything is possible with a ton of work and dedication, but noone is coming out of Tier 2's and getting jobs with the U.N. or ICC or IMF or whoever else does "international law" work. That's just the reality of the legal market.
I should have clarified that I am interested in corporate law, not development/human rights work. I wouldn't mind working for the government either. That brings up another question: I hear DoJ is very hard to break into from a T2, but what about FBI? Do they really only target T14 too?