changing stock wheels?

[bribri]

Hi, I have a 2007 yatis hatch that came with 14 inch steel wheels. I an going to track it for the first time and know the tires will be consumed. I want to go to a 15" wheel 6.5 to 7" wide in order to a greater tire selection. is there a stock 15" wheel that will work? Am I better going with another option. Im not concerned with cosmetics, only function at the lowest cost. I have no problem with used wheels.
Any help would be appreciated.
Brian, Barrie , Ontario