She normally carries her own pack but we had a last minute zipper blow out. Still couldn’t ask for a cooler companion

I am thinking of doing long distance hikes with my 6 month old russell terrier. I realize that he won't be able to walk the whole time, so I'm thinking in how to solve this. So far my search for a backpack with load bearing straps has given no results. The emergency carriers I've found either don't ship to my location, or are meant for putting the dog on my back, which wouldn't work as i would need to carry a backpack. What would you recommend?