Do I need a cartridge with more than .3 mV Output?

I currently own a Denon DL 103S cartridge mounted on a Linn Sondek / Ittok IV II. My phono amp in this system is the PS Audio GCPH which is turned up to maximum gain. The integrated amp in this system is the Cary 300 SEI which is driving B&W 805 speakers. When playing vinyl, the cary volume is set at the 12:00 position, when playing Cd's it's at the 10:00 position. I would like to replace the Denon DL 103S (.3 mV output) with a Denon DL 103R (.25 mV output) cartridge. I am concerned that with even lower cartridge output that I will not have enough gain available in the rest of my system. I wonder, if instead I should select a cartridge with .6 - .8 mV output or more? Any advice?