Some items are almost impossible to find. Like a Federal Signal PA500 FM siren needed for the Michigan SSP. It took Bruce Howard over three years to find his, then he found me one listed 30 minutes from my house.
I have been looking for over 5 years now for the Washington State Police radio. I have the correct control box and siren but the radio is nowhere to be found. I keep hoping that one will appear someday.
The hunt for and the locating of the correct equipment is one of the most enjoyable parts of this hobby for me.