[Spoof]

I've experienced the same problem with a fresh rebuild self destructing around the same mileage. I was a pro shop rebuild and all.
If you have the time and money by all means build it yourself, you can't buy the kind of pride you get from building your own motor.
There's a chance your block, crank and heads will be OK, this is a great chance to rip it apart, find yourself a good machine shop to inspect and magna flux everything, find what needs to be replaced and put it back together. Nothings ever cheap tho!