You can buy pieces of tyvek that people have turned into tent footprints/tarps for a few dollars on Amazon. Here’s one for example:
3 By 7 Foot DuPont Tyvek Homewrap Sheet by Campcovers https://www.amazon.com/dp/B01E1QL3XG/ref=cm_sw_r_cp_api_i_HuiqDb24EDJZA
I have several suggestions:
Get a piece of tyvek to use as a footprint, pretty lightweight stuff.
Boots not necessary if you don't expect snow; if you have a decent pair of trail runners that would be a good footwear setup.
Will echo GreenT37's idea of putting anything you want to keep dry in a trash bag and forgoing the pack cover.
For water filtration I recommend NOT getting the lifestraw, but instead getting a water filter such as the HydroBlu versa. Disposable water bottles are actually quite reusable and lightweight, so consider those for water storage.
I don't see any additional clothing layers on your list; that's definitely a requirement, especially if you plan on doing this in autumn. Having a puffy jacket could also serve as a pillow when balled up and alleviate that cost.
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Deuce of spades trowel is a good grab.
On lighting: I recommend the nitecore headlamp. Don't worry about another light source but pack a power bank so you can be sure that it's charged, you'll probably want one for a phone also.
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On cookware: soda can stoves are free to make and denatured alcohol is a super cheap fuel. Get a 600 mL or so pot (titanium is super light but stainless steel is cheaper). Grab some plastic eatery from your favorite fast food restuarant for utensils.
Compass: get a compass with adjustable declination and know how to use it, practice in your home town to make sure you can navigate with it.
Freeze dried meals are expensive: oatmeal with dried fruit and nuts is a great breakfast, and there's plenty of backpacking meals you can put together for much less.
I don't recommend a hatchet unless you plan to do bushcraft on this trip. If anything, a folding saw could be carried to process wood for a fire. But that is a luxury, not a necessity. As for a knife, again if not planning bushcraft a small pocketknife will do.
EDIT: on first aid kit, you can (and should) prepare your own. Pack it with band-aids, athletic tape, ibuprofen, an antihistimine, etc