Not sure if this would help at all but I've been playing through Sly 2 recently and noticed that whenever you're "aiming" (as in everything on the right stick except camera control) it automatically inverts the y-axis. So I think if you could deal with it not being inverted for just the camera you might be alright.
I Platinumed the first game and had full intention to completely rinse this (one of the best if not the best platformer of its original gen) but found it borderline unplayable as when you invert the controls, it does it to both the X and Y axes. Can't play without invert (hey, you push your neck forward to look down and pull it back to look up!), but still need to push right to look right and push left to look left.
Sly Cooper 2
Think I'll have a break before Sly 3 and 4
XBL/ PSN/ Steam/ NNID - MatMan562