if the stock steel wheels are the 7. 5" wide ones, you are ok. that is the minimum recomended width for a 285/75/16 [m/t says you can go to a 7" with their mtx's]
if you do want wider ones, those ar baja's would work fine. . they need polishing [do they have clearcoats?] from time to time. .
and you can search the classified ads in news papers or buy&sell type on newspapers for used factory wheels...