German tourist, do not trust the new commercial bag ratings, especially not the northface ones.
They list the lower en comfort ratings, and, having made the mistake of picking up two northface synthetics, because of the attractive weight, without research, the orion (20 degree, allegedly, and the lynx, 40 degree allegedly), I can assure you that the current nf bags aren't even remotely close to their alleged ratings. The lynx is lucky to keep you warm at 50+, I wouldn't even put the orion to the test, but judging by the loft, 35 degrees would be roughly realistic. Those lower ratings mean what keeps you from dying of cold, not any sensible notion of comfort.
I have an old northface cats meow, made long before their current owners bought them, and it is a wonderful, albeit 4 pound bag, that to this day I'd be comfortable in I think to 20, it even has a fuzzy liner, but it's huge, the old polarguard stuff.
That bag has far more loft than their new ones, even being as old as it is, and the fuzzy liner must add a good 5 or more degrees as well. So there's simply no way the new cats meows can be 20 degrees, maybe 30 realistically, I don't know, and I will never test anything made by them again unless I get it for a tiny fraction of its retail price, that being what it's now worth.
Northface is owned by some faceless outdoor gear conglomerate now, I'd remove them permanently from any gear options, personally I'm disgusted by their blatantly fraudulent ratings, and am stuck with two bags I'll be lucky to sell at any price. Buyer beware. I bought them not realizing how profoundly their corporation had changed values, now I know.
Look at the cottage guys as suggested, figure out how much loft you need, and talk to them, if you want a bag vs quilt, which I think is smart for your needs, maybe one of them can meet your needs.
Anyone want to buy one of these bags, I'll sell them very cheap, 80 each, basically unused?