S&W Model 17/Model 18 .22 Revolver

More of an opinion question than an actual appraisal request. Just read the most recent Combat Handguns and Nick Sisley (I know, I know, the guy can shoot but he ain't the brightest bulb in the chandelier) has an article about buying a used S&W .22 revolver. He mentions the Blue Book values and they're SO out of whack with current prices on Gunbroker, SCS, etc...just wondering what people think is a decent price point to look for a Model 17 or Model 18 in today's market? I've seen anything from mid $400s to over $1000, so I'm mainly looking for a better-than-average condition gun in the $600 area, unless somebody has better info. Thanks for any help/opinions/arguments/insights/personal experiences!