I have been searching for a bag that I can carry on my hip or as a fanny pack with minimal number of 5x7 film holders during my hikes and outings. I have one that I can carry on my shoulder, but that's a pain. It seems I have found what I was looking for. Here is a link to Carhartt Cargo Series Hook-N-Haul Hip Pack, Large on Amazon.

I have no connection whatsoever with the maker or seller of this product and definitely not Amazon. I am sharing this just so that someone else may benefit.

I can comfortably fit two 5x7 holders, tightly fit three and squeeze in a 4th one in a bind. The bag has several pockets and meshes that may also come handy to carry filters, cable release, wipes etc.