I would think just one bank might be ok, but I suppose there could be small variances in PWM needed to have both cams with the exact same advance. So, at a minimum, 2 cam sensors (one static, one measuring advance), and one PWM driver. Best case would be 3 cam sensors (one static, two measureing advance) and two PWM drivers.
I have seen redundant (static) cam sensors, in my case the 2JZ. I don't think the 1/2/3UZ has them. Having two alows the ECU to sync up the timing pattern faster, which means fatser starts, and also obviously you have some redundancy.
Also, you might want to search for HKS valcon, which apparantly can control some vvti cams, but I am not sure they have it for the 1UZ.