For winter riding with spd pedals, I used to buy police spd boots made by European cycling shoe manufacturers (I've had Sidis and Diadoras). Can't find them any more, though.
Just bought a pair of
Mavic CrossMax Pro Thermo shoes, and they're the best winter spd shoes I've yet owned. They're very well designed, with flexible (GoreTex) fabric in the section covering the ankle and a Boa wire arrangement in place of laces or Velcro closure. It's the third different Boa design I've encountered, so it took a minute to figure out that the Boa dial turns clockwise for tightening and a half-turn counterclockwise for release.
The suggestion above of just using regular boots with platform pedals is a good one, though. Clips and straps would work, too, if the boots aren't too bulky.