Hi Adam
Get her an Artic army sleeping bag ( like 233003860539 on eBay)
£40, she’ll be warm. Needs something for the face as well ( face gets real cold)
She’ll need somewhere dry to sleep, and a cardboard box or three to flatten and use as mattress and isolate from the cold. If nowhere dry she’ll need a goretex bivi like 123494993849
Added benefit is that if you think she’ll never use it again I am sure someone will treasure it.