I can't help but think that a military "cold climate" kit would do the trick.
It has a compressed arctic sleeping bag.
You can often find the compressed arctic sleeping bag on eBay, even though you probably have several.

Also a combo tool kit;shovel,saw,ax.
Wire (like bailing) to improvise repairs,
Hacksaw (or at least blade).
Maybe a small amount of additional fuel and oil.

Tools are going to be useful always,
don't forget a tarp, which has both general and survival uses.
If room permits a small come along can be nice to get unstuck.


All this of course assumes that you have minimal kit (Pocket sized PSK with a full sized FAK).
I can't imagine anyone venturing out unless;
Multi tool and Pocket/belt knife,
Navigation,
Fire-making,
Water procurement,
First-Aid,
Snacks and or emergency food (Datrex,SOS,energy bar)
needs are met.