For years I snapped up retired cop guns on the used market. Being a shooter and not a collector they fit my needs perfectly. The days of cheap surplus revolvers is pretty much over and I don't know if the political atmosphere will allow PDs to sell guns to the public in the future (and I would have zero interest in a Glock anyway) but I did my part in taking as many handguns as possible "off the streets."
A few examples. (Apparently limited to 6... but it tells me I have 7 when I only count 5. Oh well.)
Florida Highway Patrol.
Utah Highway Patrol.
Dealer would not reveal which agency used this Model 58.
This 38/44 came from a dealer who would not reveal the agency.
Wolfsburg PD. (You weren't expecting this were you?