If you can't afford the proper spare and are confident in the sidewalls of the primary four, why not just remove it entirely? Limp back down or out of wherever you are when or if it happens and call in a tow. Personally, I wouldn't run an A/T spare with M/Ts because the tires will handle/react differently. Also two tires of different types or brands with the same P-metric sizing are not going to be the same size. Do a string test to measure the circumference of your spare and compare it to the rest. I'd bet as your tires sit today the spare is .5"-1" smaller due to an initially smaller size and treadwear.
The problem isn't that I can't afford it. I'd rather not afford it. $300+ for a spare that will probably not get used is quite steep IMO.
After considering this for a bit, I have another idea. My A/T Overland Chaser has the same wheel pattern. Since I just bought new wheels for the Jeep I'm gonna have to get a matching pair for the trailer. Soooooo, I might just buy three new matching M/T Toyos (two for the trailer, one for the Jeep spare). This will give me a matching spare that will work for the Jeep and/or trailer. My poor little brain is having an easier time justifying the cost in this config. When the time comes for new tires on the Jeep, I'll buy 4 new matching Toyos and start a 5-tire rotation.
The Chaser does have it's own spare, but I think I'm gonna take it off and mount an aluminum box in it's place for a swing-out kitchen. With 12 ply tires all around, it's unlikely that I will need one spare...much less two.
If I could just find a used set of the Toyo M/Ts! Still looking on CL every day.
