It would help to know how you estimated the stores. I figure roughly 20 lbs per brood box and about 6 pounds for bees right now. That is 46 lbs. The floor and lid must be added, and will depend on your style.
Additionally, there could be ice in your hive contributing to your measurement if the weather has been cold. If the brood frames are heavily packed with pollen, that weight must be deducted from the honey as well. Pollen is important, but the honey is what pulls them through.
Where the feed is located in the hive can be as important as how much is there in total. If your bees packed themselves in and you did not move things around after September, chances are that it is in the right place: above and beside the cluster, not somewhere down in the bottom on the outside.
Feeding sugar or syrup in winter is hard on bees for a number of reasons, but not as hard on them as starving. The time to feed is in the fall, but if they are short you may have to feed. It appears you are a bit far north for the Mountain Camp system to be a good choice. Fondant is better in the north.
You have six weeks to go, and in my case, I see that my bees are using 1/3 lb a day, so from that it looks as if 15 lbs should get them there. Of course, their consumption will climb when the increase brood rearing, but by then you can give them syrup if they look to be running short.
All in all, if you calculated correctly, IMO you should not need to feed, and have quite a margin of safety.