So there's a whole bunch of of winter spd type boots shoes etc..
But i've not been able to find any such type of shoe for flats, you know something like a gore-tex lined 5 10 mid boot?
easy answer - look for gore tex boot liners on ebay. i nabbed a pair of ankle length ones for 99p plus postage - bargaintastic. the tops are a bit flappy but if you're using tights/trousers/baggy jeans then that's not a problem. They do the job of keeping your feet warm and dry but your shoes still need drying out.
Have for the last two and a bit decades used hiking boots with my flats, you can pick up light weight goretex or similar for £30 ish if you do not mind shopping around and are not a brand snob. Try T K Maxx, I use Raichle but others in my family use Hi Tec, been very good.Also used Nike?Adidas/Karrimor/Berghaus/Merrel (worst of the lot). Vibram soles tend not to get as shredded as others and are stiffer. Warter will go in eventually and will sit there I have use sealskin socks .......horrible...now use wool socks.
Oh My Gawd I sound like a fell walking rambler..........................