What happened, Corvette?

True, but that was the intended engine, that never went into production. And yes, they were offered over the counter.

http://www.ehow.com/list_7617778_gm-1970-ls7-454-specs.html

Several stories as to why they weren't produced, one being they had a problem with the aluminum heads, others because of insurance, and emissions. I remember reading an article in Hot Rod about both engines when I was a kid.

Sure it went into production. Just not in a car. I remember WELL into the 1980s that you could still buy one from PAW. They musta had a boatload of engines, because they offered all kinda cool stuff. Even with aluminum blocks. I am quite sure there are still some untouched LS7 engines in crates out there.