Wow, I'm overwhelmed by all the help! Thanks!!!
What is meant by trends? Because the block that sixt9x33rs refers to on TC seems like a good match. Am I right in my thinking that as long as the casting numbers and casting date is correct, the deck stamp is not relevant since it won't be matching anyway? In other words, a 3956618 could have come out of other Chevrolet models, not just the Camaro.
Paul: I did see the engine on ebay, thanks. I think the date works because it's within 90 days of the build of my car (3rd week of January). I'm also looking on Craigslist and asking around. It does seem crazy to sell a totally matching numbers motor!