You can also get them pretty easily from Pokemon Global Link minigames using your pokemiles, that's where I got mine 
It's pretty boring to do but it's definitely worth it :D You can see what items drop from what minigame and their respective levels here: http://bulbapedia.bulbagarden.net/wiki/P...leage_Club
So for a Lucky Egg you'll want to do Graffitti Eraser Lvl. 2, which only costs 50 Pokemiles per game. The drop isn't guaranteed but it's not absurdly grindy, if that makes sense. Hope this helps
Edit: This is compatible for XY/ASOR btw
It's pretty boring to do but it's definitely worth it :D You can see what items drop from what minigame and their respective levels here: http://bulbapedia.bulbagarden.net/wiki/P...leage_ClubSo for a Lucky Egg you'll want to do Graffitti Eraser Lvl. 2, which only costs 50 Pokemiles per game. The drop isn't guaranteed but it's not absurdly grindy, if that makes sense. Hope this helps
Edit: This is compatible for XY/ASOR btw
