Engine rebuild

[twelchb]

2002, 2.7, 130,000 miles, first really big problem! Sitting at a light the other day, clutch in, car idling at probably 800 rpm, A/C on. Light changed and I started to accelerate. I was in traffic so it was a slow acceleration. Made it about 10 feet and lost power and saw massive amount of smoke (oil) out of exhaust. Pulled over and shut down the car and called a wrecker to take car to a shop I have used in the past. By the time the wrecker came, the car had leaked probably a half or a quart onto the pavement, dripping out of exhaust tips and other areas. The shop told me that they could not get the car to turn over with starter or manually. I saw it up on a lift and there was oil staining on the headers, exhaust pipe and residue in exhaust tips. Also drips from various exhaust parts. I didn't see any holes, cracks, etc. I took the car home on another wrecker and let it sit for a couple days. Just now went out to look at the poor thing (this has really been a great car - owned since new). I sat in it and thought, what the heck and put in the clutch and turned the key. Started right up. Lots of smoke. Immediately turned it off. Probably ran for less than 5 seconds. Thoughts? Is it rebuildable? I had thought about a replacement engine, but if it turns over and runs, can I fix it instead? Really appreciate any thoughts/ideas/recommendations? Willing to put about $4K-$5K into the car. Is this reasonable or a waste of money? Thanks.