I have the most amazing pair of oversocks, which came from, I think Lithuania, or was it Latvia, or Estonia? Whoever came to Woolfest a few years back with their cosy products anyway. I always muddle those countries.
They are knitted rather like your big jumper Sally, really thick tight yarn, closely knit on smallish needles. I wear them over my normal socks, which are also wool, if it's chilly when I'm sitting in the evening, especially if I'm spinning which always seems to give me cold feet. As soon as I put those socks on I can feel the temp of my frozen feet start to rise
If my legs are cold then I have a Shetland rug woven from my fleeces by Gwilan Teifi Mill
I also have a little electric shawl, peanuts from Aldi, which can be put over my feet.