For all the Elk hunting (mountainous) conditions I have encountered, Danner Sierras have served me well. 200 grams Thinsulate, Goretex and can be resoled.
A word of caution if you have a high instep, you may have difficulty putting them on which a couple of my hunting buddies found.
https://www.moosejaw.com/product/danner-sierra-gtx-boot_10321930#productSummary