I think there is some bad advice being passed out. There is a whole lot more to belting than a one size fits all solution....
Brad at Minnesota Outdoors is the smartest guy I know when it comes to snowcat belting, and I would defer to his comments/suggestions. I would urge you to reach out to Brad before buying any belting. He's a great guy, super knowledgeable and helpful and his prices are very reasonably. I say that as someone who has bought from him before, and will again. I did a fair bit of research on this a few years ago... and this is from memory:
1.) Belting has a minimum bend radius. Obviously that bend radius has to be smaller than the radius of your front idler wheel and your drive sprocket.
2.) Belting is designed for certain temperature ranges. Pretty obvious that needs to be appropriate for the temperatures you operate your snowcat in.
3.) Belting can, and does, stretch. The manufacturer will list what the maximum belt stretch is as a percentage. Installing belts that stretch too much will result in loose tracks (that need frequent tension adjustment) as well as cause premature wear on the drive sprockets.
4.) The cover thicknesses are specified as far as top cover or bottom cover and I recall Brad suggesting balanced covers (meaning the same thickness) are what one should strive for. Thicker covers have more compressibility and the grousers are not secured to them as well with the bolts and backing plates.
5.) Belting is described as number of plies (the woven fabric between the layers of rubber) and so many PIW (Pounds per Inch Width). I know Tucker used two ply, 220 PIW belting for years and have switched to three ply, 330 PIW belting. The last time I spoke with the factory about belting they no longer had any 220 PIW belting available.
6.) Belting is usually designed for a specific purpose, usually as conveyor belting for agricultural products, mining products, aggregate products, etc.
7.) Heavier belting, such as with more plies, or thicker covers, or both, will weigh more and it will be stiffer. Both of those characteristics will negatively affect the performance of your snowcat. You're adding weight, increasing the rolling resistance and also the rotating mass. None of those are good things.
8.) Some snowcat owners will buy cheap, used belting and try and save money. Others will buy new belting as cheaply as possible, which likely won't be optimized for snowcat use either.
My opinion only, but I think using anything other than quality belting that meets the snowcat specifications is penny wise, and pound foolish. It's a LOT of work to change out snowcat belts. A 1600 series Tucker (long tracks) has 124 grousers and each grouser has eight bolts. Do the math, that's 992 bolts. On the earlier style grousers two of those are welded studs and six are bolts. (Later style grousers feature more studs.) The nuts sometimes get damaged and will not come off. In the case of a bolt you can pretty easily cut it off, but when the problem is the stud you have to cut a hole in the grouser to access the stud to remove it, and then weld in a new one. Then you have the hole to either leave alone or try and repair. As I said, it's a lot of work, and most of the time you're doing this with the belts and grousers laid out on the ground and you're on your knees. Your knees won't like it and neither will your back.
Think about that when you are considering buying belting....
Several years ago a forum member had his grousers galvanized. I know my snowcat buddy Scott frequently has items galvanized per his customers specifications. As I recall the price is a function of what the item(s) weigh. I also recall it wasn't cheap, at least not by my standards. IF you operated your snowcat only in snow 100% of the time and never hit a rock or gravel or dirt, etc it would last a long time. And the same is true of paint. But the reality is pretty much all snowcats encounter rocks, dirt or gravel in normal operation and that will cause rapid wear of either the galvanizing or paint. For me, either galvanizing or paint would be a waste of time and money.
For tires I'd reach out to Peterson Equipment in Logan, UT and/or Dan Gates at Snowcat Service in SLC. Peterson was a Thiokol/DMC/LMC dealer for decades and they have considerable corporate knowledge.