If they show "out of stock" on their site, that doesn't really mean they quit producing the 10T upper, does it? I seem to notice that when Armalite "does away" with a gun, component, or part, they usually just remove it when inventory is gone. I see the 10T upper on their site for just under $1k on the site. 762AR556 is right in asking about specific elements of your particular upper, but I'm assuming a factory 10T upper.