My families 2010 Taurus had basically the same repairs plus the internal water pump on the transverse 3.5 at 240k miles. The estimate was higher than what you quoted (in Canadian$) for just the water pump job. It got sold for $600 to a friend/mechanic I used to work with and he fixed it himself to keep for his personal vehicle. The engine only had a slight rattle on cold start for a second but the engine light was on work a code for variable valve timing.
The chains were stretched and tensioners maxed out. No varnish or sludge in the engine though as it had 3k oil changes every few months (all highway driving) with conventional oil. I wonder if the timing components would have been much better shape if synthetic had been used. It should last a while now but it was basically wrote off unless a tech was willing to buy and fix it himself. He had to buy the special tools to fix it and everything.
