I bought a good LBZ shortblock with 80 000 miles on it for $1800. Took it apart and it looked flawless.
This is what I was starting my build with over 2 years ago and thought I would have it done before my engine failed. Didnt make it before I broke my crank.
Good news is that my engine may only need allign boring and another crank and I should be able to almost recoup the cost of my shortblock purchase.
For your build if you go with that engine expect to replace the water pump, CP3, all new injectors, possible head machining if it isn't straight, new guides are not too big of a deal, I'd do the oil pump too as well as a new oil cooler. I'd consider a rebuilt or new turbo as well considering the mileage.
Getting on it ahead of time is not a bad idea. It saved me from having to drop a pile of money and scramble when mine went as I already had everything purchased.