Man that completely sucks. Overwhelming probability is something internal broke and hit the block really hard from the inside rupturing it. I don't know where you are located, but used engines around here can be found for under $1000.00 Swapping an engine is not as difficult as it sounds, just think of it as a really large part. Oh and I'm sure I'll get attacked for this, but I would not rule out you using the wrong oil as possibly contributing to this catastrophe.