Hearthstation
Drops from Gently Shaken Gift. The problem is, that the quest hasn't been reset. So if you have done it last year, you cannot do it this year on the same character.
The 
Hearthstation is a toy obtained during a World Event from the 
Gently Shaken Gift, a bonus sixth present that has a random chance to appear alongside the standard gifts.
Guide awaiting review
Open Gently Shaken Gift
When opening your holiday presents, watch for a sixth gift called Gently Shaken Gift to randomly appear — the Hearthstation toy is found inside it.
Try on an Alt
If the Gently Shaken Gift does not appear on your main character, switch to an alt character (level 10 or higher) that has not previously opened these presents, as the quest resets properly on characters with no prior completion history.
Try Stolen Present Instead
Hearthstation can also drop from the Stolen Present and may require multiple attempts, but it does drop from this source as well.
Tips
A fresh Demon Hunter is a reliable alt option to obtain the Gently Shaken Gift if all other characters have already completed the quest.
