I feel ya, I've been driven off the stand by the cold once or twice.
Wool is great, but if you saturate the boot insulation itself with sweat your sock alone will simply not be enough.
I'll often switch from running shoes to my boots AND warm socks after I exit the truck. I do it mostly for comfort so i don't roast while driving, but also for scent control as I'm not walking through gas and other odors everytime I stop and get out at a gas station for example.
I layer down to my thermals and a hat for the hike in. Once I'm warm enough the hat goes in a pocket. Once I'm on the stand and set up I'll layer back up. I would really prefer to sit and wait about 10min to cool down before I layer back up, but the stand does not always allow all that movement and noise. If I am still really warm, I'll leave my zippers open till I cool off.
You could also change socks to a dry pair at this point. That should give the full protection of a dry boot and your dry socks.
In the deer blind, I'll either hunker down in a heavy sleeping bag or throw on my down lounge booties. I'll even throw a few handwarmers in the bottom of the sleeping bag when it's really cold.
A nice thick pad under your butt will also help prevent heat lost through conduction.
Stay warm!
Vince