import to steam?

Hey, I bought this game a while back for $40.00 (Products: Rust Alpha x 1 @ $40.00)

However, this was before it was available on steam.
I kind of forgot about the game and want to play it now.
Is there any way I can get the steam game because I can’t seem to play it from my browser like I used to.

(User was banned for this post ("read the sticky before making a thread" - postal))