If you want a steel wheel, I would find a shop that sells the aluminum wheels and see if they have one from someone who swapped their wheels out. They might even give it to you. A new tire for it is most likely going to run you around $500 mounted and balanced, valves, etc. As was pointed out, most new RV's don't come with a spare and there's a reason. First, unless you have a good impact wrench with you, getting the wheel off is going to be nearly impossible. Getting the lug nuts torqued back on after changing is going to be even more challenging. All of this plus the weight of that monster wheel assembly your handling (or two wheels you get to handle if you blow the inside dual) is simply not something you want to do on the side of the interstate. My suggestion? Get something like Good Sam Roadside, pull over, crank the generator and AC and wait for the repair guy to show up. They know what they're doing, have the proper tools and know how to work around the traffic. Terrible thing to get killed just to save the cost of Good Sam for a few years.
