I have a North Face sleeping bag rated to -15 F in great condition. It is about 25 years old, but I hardly ever used it, because it is too hot for anything but very cold conditions.

I think it is worth more than $100. Pick it up in Boulder. Message me with your best offer.

I also have old climbing magazines: most issues of Climbing starting in 1990; R&I since about 2000; Alpinist #9 thru #60. The Alpinist issues are probably worth something ($1/ea?); the rest are yours, if you come get them.