The whole combo is worth maybe $4000-$4500 max. You can find a brand new HS for $3000 if you look hard and the Diavari's I've seen sell brand new for $1700 over on the hide. Without pics of the marks and without knowing the round count you'll have to figure out exactly how much off the NIB price to offer. The HS isn't the most popular .50 out there, so they don't hold their value as well as some other rifles
If you're looking at getting into .50 bmg though, you really need to look hard at the AR-50. You could pick up a brand new AR-50 with a Nightforce NXS 8-32x56 scope with mil turrets and an MLR reticle(matching your turrets to your reticle is VERY important, both for shooting and for if you ever want to sell the thing, selling a high end optic without turrets matching the reticle is a nightmare) for pretty much the same money. There's a reason why you see so many AR-50's at matches, they're accurate, very well built and very reliable. IMO they're the best .50 bmg in that price range.
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