Check the allowable rim width range spec on the tires you are considering. Most 12.5" wide tires will have a minimum of 8.5" rim width. I run 35x12.5s on an 8" rim without any noticeable ill effects, not sure it would work on a 7".
I really loved the look of the TRD Pro wheels, but knew I wanted to go to 35s. I'm running FN FX Pro wheels, which are identical to the TRD Pro stock wheels, except they are 8" wide, 0mm offset and 4.5" back spacing. Another company sells TRD Pro center cap decals.
TRD Pro wheels are always being sold and bought on the local groups I'm in, so you can probably make the switch without too much hassle (if the FN's are in stock). FN FX Pro Wheels FN FX Pro Wheels Center Cap Decal