As been said, you really need to make sure the tires will fit in the space available, that includes the diameter, front AND back clearance. I went through the same search a few years ago and never did find the wheels I needed at a reasonable price. The next step is to change the hubs/drums to 6 lug, then 16" wheels are easy to find. Drums run about $75 each.
I ended up getting a set of the NEW Carlisle RADIAL TRAIL RH tires (ST225/75R15 E) when they first came out. For the last 15yrs I averaged about 2yr / 6000 mi on a set of tires before one separated. So far, the last 3 years / 9,000mi the Carlisle tires look the same as the day they were new.
