Applying SPD cleats in the usual manner by drilling the sole and using a metal back-plate will compromise your winter boots and put a heat-sink inside.
Boot soles are usually too wide to position the cleat correctly in the centre of the sole, unless you use a pedal with an extra long axle.

I would reconsider toe clips, metal ones with leather straps. Why do you need to use your hands with toe clips, there is no need to tighten the straps, they work pretty well lose and are quicker and safer than tightened straps. Tight straps were only ever used by race/high performance riders.