A 2-3 shut down on this TV means that you have lost horizontal deflection, and there are a few things that can cause this, so without having a tech troubleshoot this, it really isn't possible to say what it would cost to fix.
But there have been problems with intermittent solder connections around the deflection yoke plugs on the individual tubes, and if that's the cause, any decent TV tech should be able to fix that with just a service call to your home, cost of about $170, depending on where you live.
But if it's a board, the tech is going to have to come and troubleshoot the set, order the part, and come back to fix it, and I would expect that to be in the $600, tops. And while this is a great TV, that's getting on the edge of what I'd recommend you spend on the set.
Let me know if that helps, and thanks for using JustAnswer!