I know this won't help Nitesun, but can you still get electric socks and gloves wired up to goon suits with your own personal temp controller hanging under the seat?. They were wonderful. I even penned a little verse in chinagraph on the windscreen of my trusty SeaKing many years ago:-
The sun has riz,
How cold it is,
But still I'm warm as rocks.
My heart goes to the girls back home
who knitted my electric socks!!!
Just thought I would share that with y'all