Nice idea!

Here are some:

This is Colt New Police from Port Huron MI PD



Two 1896 S&Ws (Jersey City PD & Newark NJ PD)



A S&W Regulation Police from 1924 that was used by the police in China



Police Positive Detroit PD (1916) I added the stags



New Police Detroit PD (1902)



More PD issue New Police .32s: