I have an original chrome SC like this of the same vintage (mine is circa 1971), though in a smaller size. I think chrome Cinellis are rare, as numerous searches of similar years generally turned up only a handful, versus very many of the standard silver, some dusty rose and very few black (love the rose and especially black ones!). I don't know what my bike is objectively worth, but it's worth a lot to me.
As noted, the rechroming of the OP's bike hurts the value, significantly to me, because I like original bikes, while some others don't much care. But I think there's a good chance that it was fully chrome to begin with. You can see blue paint in the chainstay coves, a detail that might have otherwise been overlooked if it didn't originally have them.