Michelle Gomez as Mother Winter.
Id rather her for early Lea (in my head the Lea actress gets younger in every appearance/book, especially post rehab).
In my head the Mothers will almost certainly need to be aged up into the truly Ancient looking realm regardless of who they pick. The ones I recall seeing suggested that I really liked were Sally Fields for Mother Summer opposite...somebody who I was not familiar with and who I cannot recall or find reference of (dammit) but who exemplified the Crone aspect of Mother Winter, somebody with the perpetually sour expression of somebody who might just consider the marrow of babies to be a type of candy.
Judy Dench is another popular one for mama winter, but personally she's just too damn strong and formidable seeming for a character that generally huddles, shuffles, and doesnt want to so much as stand up "in the wrong season". Also I could never see Judy Dench acting as petulant/petty as mother winter occasionally does with Mother Summer.
