truck wheel rant

Oops thought it was Ram. My new winter setup cost me $1500 for rims rubber and sensors. Buddy of mine has an 06 came factory with 20". That starts getting really pricey.
its not a ram, though
but i like that price, i might call them monday

so far ive come across one set of "factory take offs" steel, silver painted 18X8s for $350
then add some 265-70-18s for about $600 and mounting and balancing, man, thats a grand
i doubt i will get that back for those stinking dubs

i wonder what weight index tire i would need for a 7000 pound rig?