I would say it certainly is. Now I haven't had any kind of hand injury, but still, after 16 years of playing, I recently started trying to incorporate the right-hand pinky into playing. And it just goes quite well.
By the way, there are even some classical guitarists who vouch hard for the right-hand pinky. I can think of Štěpán Rak, but I think that I have seen Kazuhito Yamashita using the pinky as well. And there will be more guitarists like that, I just don't happen to know about them. I guess that in flamenco guitar, there will be lot of them (because they probably didn't adopt the classical opinion of PIMA being the only "correct" fingers).
So: is it feasible? Yes, certainly, and it could be even recommended that people with healthy hands use the pinky as well. (I still didn't manage to get a good output with it if I try to use it in block chords, but I tried tremolo with 4 fingers and that went very well.) And I would say that with some practice, you can get just as good as anybody using PIMA. The only disadvantage will be that you won't be able to use all five fingers, which makes the right hand even more powerful, but not by much, I would say.
By the way, if you're re-learning from scratch, you will possibly have much easier time than me. I've been playing 16 years without the pinky, so it's not that easy to get into it.