The game's collection data lists Citizens Brigade Whistle as sold by a vendor NPC in Sinfall.
Vendor
Zone
Map
Waypoint
Other items it sells
NPC #175369
Sinfall
-
-
191
Vendor NPC, zone and position come from the client's collection source tables (CollectableSourceInfo and CollectableSourceVendorSparse); coordinates are the in-game map readout.
Build history
First seen in build 12.0.7.68887 (Midnight (patch 12.0.7)).
Failed Experiment BrewID 95401 · Miscellaneous"As far as you can tell, the label says Squid Ink and Salmon Eye."
Items Numbered Next to Citizens Brigade Whistle
Blizzard numbers items as they are created, so the named items next to ID 166247 (166242 to 166253) were usually added in the same batch as Citizens Brigade Whistle: the same quest line, zone, vendor or reward set.
A Shady MessageID 166242 · Miscellaneous"Scribbled within are subtle hints regarding a smuggler who is capable of obtaining some extremely exotic pets."
Investigation ResultsID 166243 · Consumable"Contained within are the results of your followers' investigation."
Token of ShadinessID 166244 · Quest"A token used to identify the owner as a shady character."