^ Well that makes perfect sense. And about the only scenario that begets a real potential need for redundant spare tires.
(FWIW, you can sleep better also know that the trip is not that bad or that hard on vehicles as long as you taker easy over the frost heaves that you see. It's the ones you miss that'll wake the kids up in the back seat!)
Does your trailer just have the black steel wheels like the brochure pic? 14"?
If so, GD is out of their minds charging that much for a cheap stamped wheel! Maybe if it was a nice matching custom 15" aluminum wheel.
What I'd do, since you're replacing the OE tires which are basically new, correct?
Great to have the "best" tires on the road, although not a necessity.
Use 2 of your takeoff tires, buy a couple rims either new or off craigslist/FB.
Voila, you have 2 spares for less than $100.
You shouldn't need them and I certainly wouldn't pay a premium for top notch tires just to park them as spares, "just in case."
More importantly, I'd have a way to air up tires (small compressor), tire plug kit and a colby valve to repair a leaky valve stem. I'd likely not even carry 2 spare rims, but rather an un-mounted tire and bring my tire spoons in the highly unlikely scenario I blew 2 tires between towns.
Pulled 2 different trailers up the Alcan a few years ago, both during mud season, so frost heaves were at their worst. No issues with tires, fortunately.
2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
2017 Heartland Torque T29 - Sold.
Couple of Arctic Fox TCs - Sold