I am not sure if a ultimak mount will fit a saiga, that is unless is has an ak-47 style front handguards... make sure it fits a saiga before you order.

Both Optics would be fine choices (i have shot both)
Tritium is nice because you don't have to turn it on and off.
The battery life of a t-1 micro is 5 years of continous use 24/7, so that is of litttle concern. I know I don't want to be changing batteries when the SHTF


I am not sure you want to be spending 500$ for an optic and 100$ for a mount

I saw an ultimak mount for 88$ +free shipping online the other day... from some company I had never heard of. (google shopping search)