This topic has been brought up several times over the years, and the devs even made mention of it some years ago. We still do not have it.
As a non-developer, I'm curious as to how difficult it would be to implement such a simple feature relative to supporting a long-term decade-old game. It's been alluded to, it's been borderline teased, and it's been forgotten. Will we ever, at any point, get the choice to use a weapon's default base skin as an option for Primed weaponry?
For beans' sake, I cannot stand the mace design for Silva. I think it's entirely antithetical to the whole point of the original design. Please, give me back the chance to use Silva & Aegis as it was originally intended without having to resort to the Day of the Dead skin which still frequently (and reliably) breaks.