Keith, so far as I know the 1862 Colt Police pistol came only in .36 caliber. It had a fluted cylinder, and barrels of 4.5 or 5.5 inches. The reproductions come in .44 caliber, but not the originals. Below are some sites for Colt pistols. Stan

http://home.comcast.net/~dsmjd/tux/dsmjd/tech/coltperc.htm

http://home.comcast.net/~dsmjd/tux/dsmjd/tech/coltperc.htm

http://www.armchairgunshow.com/otsAC_percussion_colts.htm