My point is that the requirements on a space reactor are sufficiently different than a naval reactor that I'd think you're better off looking for inspiration at

My point is that the requirements on a space reactor are sufficiently different than a naval reactor that I'd think you're better off looking for inspiration at things like Kilopower than the PWR's currently used in naval vessels. Yes, if you build the thing in space weight isn't such a critical factor as if you're launching it from Earth's gravity well, but weight still matters as it's mass you have to accelerate and decelerate as you zip around the solar system. A PWR is inevitably extremely heavy due to having to withstand the 15 MPa pressure (assuming naval PWR's have about the same pressure as civilian ones, I suppose they could be somewhat lower). Further, a critical issue for a space reactor is how to cool it. Radiative cooling in space is very bad compared what we can do down here. Thus to minimize the size of your radiators you want a reactor that operates at high temperature. Also in this respect a PWR is a very poor choice.