Doug M,
Pretty sure the ISP did carry it, if my foggy old memory serves, they were the first large agency to begin carrying 9mm autos. In fact, I think they contracted with Federal to develop a 9mm that was supposed to be the semi-auto cartridge clone of the 125 gr 357 Mag. I think that's why it got dubbed the "Illinois Load" in the first place, but I could be wrong.
Maybe a retired ISP Troop on the board can chime in with more insight....