r/65Grendel

I know someone with a Noveske 18in stainless barrel with the gas block, rifle length gas tube and a headspaced bolt from noveske. Its all unfired, new in packaging. He is asking $500 . Is this reasonable for a start of a grendel spr type build? What other barrels would you recommend? Is a headspaced bolt really needed?

Ejector claw on my bca 6.5 Grendel ar upper broke yesterday, rather than get another bca part, how compatible are these ? Should any aftermarket ejector claw work with any bolt?