Key fragments and blue essence

So I'm pretty annoyed, i rarely get any keyfragments and when i do it takes a week to get from 2 to 3. I already have 2 Teemo mastery tokens (yes i know I'm a devil) and i got 2 champion shards, one hecarim and singed. Last URF i used the Hecarim shard (rented it). And now this mastery 6 and 7 thing comes and I'm 42 blue essence short, 42!! so is there any way we can earn blue essence without champion shards? Something like draw for RP would be nice, but instead of 5 RP you get 40 Blue essence (or 42 )