I don't have any and don't know anyone with one, but if you're desperate for one here's what you can do.
Buy 2 Dota Crate Keys
which is the going rate for a key. Then go on some trading site (for example, /r/dota2trade
and just post up saying you got two keys and looking for a Dota 2 Key. Should get one quick enough.OR
, failing that someone hasn't got one and you don't want to spend money, your best bet is waiting til the end of the month. There is currently a load of theories being thrown around that it might go from closed beta to open beta after the International 2 is over (or even when it goes live to get everyone to watch the ingame spectator).
Either way, good luck getting a key.