When GM was building them they came blued, with breech plug (hooked), nipple, underlug for barrel key - can't remember if they included sights, but sold for (I'm thinking) $240 (but might have been $220 - right in there anyhow).
They no longer produce the "drop in".
Oregon Barrel now makes a similar "drop in", no sights and not blued (in the white) and they go for $350.
So to "replace" it with new, you are looking at 3 1/2 bills plus a bluing job.
If this barrels is in good shape it may be worth what it originally sold for, even if used, given the current options.