Buying from a reputable dealer is not air tight either. I initially bought my Chevy 427 big block from Speedomotive as a crate engine. It was a shortblock and I added the rest.
After slightly over 100 miles, the engine threw 2 rods through the oil pan. Oil pressure appeared normal the whole time. I had my machinist perform the autopsy to find out what went wrong and he pulled a piece of wood out of the main oil galley from the oil pump that feeds everything...and I wouldn't have known because it was just after the oil pressure gauge sender. The engine was actually starving for oil despite a normal reading on the pressure gauge. The pins seized on two of the rods and they shattered.
Speedomotive paid for all new parts despite an expired warrantee because they suspected that some disgruntled employee sabotaged a run of crate engines. I rebuilt it, and so far, so good.
So as long as it has a warrantee, you could try it, because that's a pretty good price. Make sure you install it and run it as soon as you can, rather than doing what I did and burn up the warrantee sitting in the garage waiting for the rest of the restoration.
