Chris,
Sorry to hear about this issue!
With all of the apparent problems and band-aid solutions, I sent an email in to Canik asking for an explanation of the SKU change. This tells me they have a problem and are trying to fix it. Here's the body of my email.
"With the change to the SKU number, are the older S models being replaced? With all of the issues being reported on the web, I'm not running this gun in competition because of reported failures at matches. I bought this gun to run in competition; it's intended purpose. Please advise to what is being changed on the new SKU."
I doubt they will respond. I hope you can find a spring to get your gun running again. Maybe a spring from another platform?