AR15Sport.com retro barrels also do not come with the front sight or swivel, a fact which I completely forgot when I ordered my 1/9 pencil! Fortunately I had a spare USGI A1 front sight, spring, and detent in my spare parts box. I had almost given them away on PIF a couple months ago, but knew I would need them sooner or later (in this case sooner!)
I had a spare swivel, but it was a little rough, so I opted to wait for a new one, since my weapon is 100% new.