I bought a complete L67 (supercharged V6, complete motor, SC included) for $750 from dallas, it came from a bonnie, but after changing over a couple parts off my old engine, it dropped in without a problem. Paid another $700 to the tech at the shop I work at to put it in and shes been fine for the past year and a half, almost at $20k on the engine with me. Definately worth the money and I bought a more expensive engine because I wanted lower miles. Its much cheaper, especially if you can put it in yourself, I didn't have the tools to do it or the time so I just paid the tech.
I spun the bearings on cyl 1 & 2, not sure the reason, thinking oil pump gave up but with only 83,000 on the car it was really odd. Definately buy a new motor and change the gaskets and drop it in, you will be much better off.