Unrooting moto g 2nd gen, need original firmware

Similar to this post: Cannot update to Lollipop on rooted Moto G 2nd Gen

I rooted my moto g device a few weeks ago as i needed to access the hosts file for dev purposes. The result was, a rooted device. Perfect.... until the nice new shiney andriod os came out, i ended up in the same reboot loop as the OP on the link above.

I have found a few sites that claim they can restore the original os and firmware to the phone however all of the point to this site which just throws an error: http://ift.tt/1wut6Xm

Does anyone know anywhere else I can download the original firmware, or no a way to restore my handset without it?

Thanks in advance, John