I'm having trouble finding out the paint code for my bumper. I'm pretty sure the vehicle is Millenium Silver Metallic and the bumpers are also a sliver color but I couldn't find anything online.
Appears you have a two-tone 4Runner. K84 has two colors to it, 1A5 is a gray metallic (appears to be the body color as my understanding) and 181 is the silver color for your bumper and cladding. 181 should be the paint code you need to get the correct touch up paint.
I found the info on paintscratch.com by entering in the year, make and model. I did a search for your paint code afterwards for the info above.
C/TR is color and trim in the form of exterior/interior color.
I believe the latter, A/TM is engine/powertrain and transmission code... I could be wrong about that one though.