The Gerber Trio with red LEDs sounds about right. Its a compact (shorter than a minimag) 2AA light that produces a decent flood of red light from it's 3 5mm red LEDs (nice and deep red, not red-orange like most luxeons). While its not really intended for momentary, the slight play in the threads in the rear twisty provides momentary easily, and the twist action for constant on is easy to do with one hand and is silent. The overall build quality is actually pretty good, especially considering this can be had for $20.
I just noticed your last post, and the Trio might actually be too bright. A few lights I've used for this purpose (midnight pee): Gerber Infinity Ultra w/red LED- bright enough, Dorcy AAA modded with a red LED, and Rigel Systems Skylight- this one is good because it switches between red and white (in case some other need arises) light and has infinitely adjustable brightness levels for both. Just note that it doesn't have momentary and uses a 9 volt battery.