I also today received my new NAV and BAND buttons from www.replacementradios.com $20.00 for one button each additional button $15.00. Replacement was simple, remove dash cover, remove 3 bolts to NAV unit, gently pull radio out, disconnect 3 wire harnesses and an antenna wire. Pop NAV cover off and remove 4 tiny bolts not screws, I used needle nose pliers. remove worn buttons , poof done less than a half hour.

The drag now is my suv has nothing else to fix!!!

 

Thanks Rick, good link.