Thanks everybody.

I checked another Walmart location yesterday, and like the one I had checked in another state, all the cold weather sleeping bags were made in China even though they had more than one model of Made in USA warm weather sleeping bags.

I ended up ordering this bag
https://colemans.com/u-s-g-i-usmc-cold-weather-sleeping-bag

based on LightninHopkins' suggestion of a similar military sleeping bag. With the Black Friday discount code SAVE25 for 25% off, the price was less than $100 for a factory new condition Made in USA sleeping bag in the temperature range I wanted. I added a USMC sleeping pad for less than $10. Shipping was reasonable (less than $20) for the sleeping bag and pad, but if I added another pad the shipping jumped by more than $50, so I ordered just one pad with the bag.

I still need to add another inflatable sleeping pad to our gear (have a foam pad for each sleeping bag).