...Just to be the usual contrarian, I wonder whether the pistol and rifle should really be considered phase weapons. The pistol is identical to a gun that early in the show was defined by
not being a phase weapon, thus requiring replacement by the Starfleet phase pistol. Unlike the Starfleet plasma rifle, the pistol was not later modified with add-on parts.
Moreover, both the pistol and the rifle fire bolts very similar to those of the original EM-33 plasma pistol, and never beams.
Both the pistol and the rifle are sometimes seen stunning or otherwise incapacitating their victims, rather than killing them. But that's possible with today's slugthrowers as well; and the pistol is never said to feature a stun setting, nor do our heroes and sidekicks adjust its possible settings on screen. Since the MACO force carries the extra weight and bulk of those stun sticks and grenades, one would assume they have no surefire stun weapon of other type available - just a gun that's not 100% lethal...
The rifle is indicated to have a specific stun setting in "Impulse", though.
It wouldn't be all that surprising if a conservative branch of the military opted not to adopt the fancy new phase technology immediately, especially not when the fate of Earth depended on the reliability of their guns as much as it did in ENT S3.
Oh, and your artwork certainly has the stun setting on; I'm still reeling from the effect.
Timo Saloniemi