I just returned from a weekend backpacking trip and had a really good time. I purchased most of my backpacking gear this summer because I wanted to start backpack hunting instead of walking 5 miles and 5 miles back to camp each day. If I had better hunting buddies I would love to do what you are doing.
So here is my list..
North Face Quartz 22 3 season tent I think would work good in Sept hunting weights <5 lb, Thermarest sleeping pad 1 lb, I use a North Face sleeping bag 0 degree, Eberlestock X1 pack is a great hunting pack but too small to back pack hunt with. Looking forward to trying my Just one by Eberlestock. Katadyn water filter, might get iodine pills as a backup in case the water filter breaks, I'm a fan of SnowPeak and use their stoves, fuel, and cookware. It's all titanium and barely over 1lb for 1 cup, stove & fuel, 2 lids, 2 pots, and the lids also work as plates. I was really impressed with Mountain House freeze dried food. Just had to boil water and add, wait a few minutes and ready to eat. It didn't taste bad at all. I also carried power bars. If you want to keep down the cost get oat meal and skip paying $5 a meal for breakfast. Don't forget the TP, I also bring baby wipes, matches, hand santizer, minimum 50' rope, couple knives, small hatchet, Spot GPS, regular GPS, camera, good ol compass just in case, light w/ xtra batteries, water bladder, extra set of clothing.
My pack was 50+ lb just for a weekend camp trip. I was hauling a .357 but no rifle, binoculars, water proof gear etc, so you can see how the weight adds up quick. I used a lot of google to see what people take and thought of my own list. I'm at work so this is off the top of my little brain but think everything is there
I would lay everything out, pack it, and practice walking with it all. I still didn't get my packed right after changing and changing it and I think that makes a big difference when hiking miles and miles. My back was sore for a bit but well worth the fun. I got a lot of my stuff from backcountry.com super fast shipping and free for orders over $50. If you don't like it after trying it no questions asked return policy.
Hope this might give you a start and keep us informed how your trip ends up