I've read some trip reports for this river at low flows. Sounds like it is doable in kayaks. There are some screen shots of real low flows here:
California Creeks - Selway River
I'm also debating if I want to do this river at real low flows in an IK with someone that has canoed and rafted but not kayaked.
Last I heard the drainage was something like the 3rd lowest it has even been since they started keeping track. Haven't seen that at an official website, but that is what I've been told. Good luck.