Having to work outside in really tough conditions is bad enough, but many times worse if you’re cold too.
I found RefrigiWear suits years ago. They’re made for workers in blast freezers, so they’re tough, not super expensive and come in lots of sizes. My whole crew got these suits and they kept us fully functional while outside overnight for February-in-Wisconsin telecom projects.
I have no idea what Iditarod racers wear, and I’m pretty sure these won’t have the right cache for the ski set, but for working people these suits help you get the job done in the cold and won’t drain the piggy bank.