In my estimation, you'd be hard pressed to find a new motherboard for that socket. When my z77 crapped out, new motherboards for that socket were more expensive than when new and a lot of the feature rich boards were not available new.
It'd be more costly to upgrade, since your have to get new ram as well if you go z170 or newer. Dependent on CPU/RAM/Mobo you could easily spend 6-700 dollars.
Sent from my Pixel XL using Tapatalk