Brick PD Channel 5 is 453.1875, so I would assume that's what they're referring to when they say "Tac 5". It's a mobile/portable only frequency (not a repeater), and is only licensed for 2 watts of power, so you would have to be near, or more than likely in the immediate area of the units that are using it in order to receive it.
There is also another possibility. Brick PD has 5 new frequencies licensed to them as of April 2007, all mobile and all 2 watts of power:
453.0375, 453.9625, 458.9625, 453.9125 and 458.9875 and it MAY be one of them. They're in the process of upgrading their communications system to digital with encryption capabilitles. I don't know whether they'll use these new frequencies when the new system is up and running or if they're using them now in analog. You can try them, but again, you would have to be near the area where the units are transmitting because of the 2 watt power output.