I'm looking at buying a 92 passenger side manuel mirror and I was wondering if that would work with my 1990 toyota camry? If not, what years would work? and does anyone know about how much would an entire backseat for a 90 camry cost? thanks for the help

I'm pretty sure that the mirror will fit. You'll want to make sure and check your bolts that mount it to the car are all in the same place...but I know that they will fit, you just have to check and see if the pegs match up.

Also, I forgot to add this, but about your back seat, the only place that you will probably find one for a decent price would be at an import junk yard.