I like the Finnish company, Hurtta for winter clothing. I used them in the past for another breed of dog and intend to get Hurtta for my puppies’ first winter. I do live where it gets extremely cold, though, like -30 or -40°C during the worst of it.
If you’re not where it’s too, too cold, a company like Canada Pooch or Silver Paw or FouFou are all great and good quality. I use these brands in the fall and early spring here.