Just to add, in all honesty, I'd ditch this device and buy something else. If it's stuck at cm11, you aren't receiving security updates and it has more bugs than stock.
So, money might be an issue , I understand. I could suggest finding and old nexus 4 or 5 perhaps. You can find those for 100 to 250 CAD dollars. OR, you can try an a chinese brand such as leagoo. I've bought the leagoo m5 as backup. It's not full of custom ROMs, but there are some. Also turns out to be a handy, long battery life, functional device for only $100 CAD. Check it out.