Walmart has great socks in their camping section. They're wool but they're not at all itchy and they are very very warm.
Instead of breeches, I wear slim leg jeans (so they fit under my tall boots) and wear suede chaps. If I am particularly cold, I'll wear some leggings under the jeans (the spandex kind).
For a coat, I bought a coat that warehouse people use when they work in a freezer all day. Refrigewear or something like that (I don't have the coat handy). It's rated for up to -20F!
For gloves, I bought Under Armour glove liners and have a pair of SSG winter gloves.
* I'm often reading and posting from mobile and Siri loves to make a mockery of the English language.