With the caveat that sellers on GB post frequently "unfired/LNIB" for guns that are not, blued examples with box/papers that appear most plausibly unfired/LNIB (and that lack "read the owner's manual" roll marks) generally go for $2,600 to $3,200 on GB these days, with Chantilly-marked examples generally in the higher end of that range and Sterling-marked examples generally in the middle to the lower end. Guns that have been fired but that are in excellent condition generally go for $2,000 to $2,500, depending upon whether box/papers are present, slide "plumming" is apparent, presence of minor blemishes, number of mags included, etc.
They're definitely not getting any cheaper. I'm kicking myself for not picking one up a few years ago.