I need help valuing a Unused Colt 1970s era 20" 5.56

[CTac]

I need help valuing a Unused Colt 1970s era 20" 5.56 pencil barrel in 1/12 twist so it's basically a new unused SP1 barrel from the 70s which I would think is pretty rare. I'm trying to find what they are worth. Thanks

[Whole Bunches]

Does it have the flash hider (if yes, what type of flash hider?) and front sight base with round front sight post, front triangular hand guard cap, bbl nut, and gas tube or is it a stripped bbl? What are the markings on the bbl? Triangular hand guards?