Sorry for my bad English.
I have personally found this exploit. If this is repost, sorry (but i don't think so)
1. Be 70-73 lvl
2. Complete quest for access MT(heroic) Magisters' Terrace - Quest - World of Warcraft
3. drop any keys for access to other BC heroics from your bag(!!!)
4. make party from 70-73 players(this will be faster)
5. open LFG (press "i"). stay at "random BC dungeon (heroic).
6. repeat many times and farm you own mount