Dirt cheap -serviceable but not fabulous- backpacks can be made with an XL stuff sack, and some thru-hiker premade shoulder straps... depnding on the size and material of the stuff sack, youve got a bag between 2-3000ci, weight of about 5-10oz, and a cost of about $20. Less if your a good scrounger, like if you pull shoulder straps off of a $2 bookbag from the thrift store.
A Ray-Way type quilt can be made easily skills wise, and if you source your own materials you can make it for about $25-35. About 24oz give or take depending on how its made. Or that MajorSurplus bag for $25.... Or split the difference and "edit" that MajorSurplus bag into a quilt with the help of a seamripper, some scissors, a needle, and a few yards of thread.
A Tyvek Poncho/Tarp from Goodling Outdoor covers your rain gear and your shelter. Im not sure on the weight here, but its gotta be less than 1lbs, and costs $50. You could probably make one for much less.
USGI Surplus sleep mat, $5
A $10 sportshell
WalMart/Athletic Wear track suit - $25 about 1.5lbs
Walmart fleece sweat shirt - $6 (on clearance unfortunatly, Im sure they will have something similar again) about 8oz
Socks (nylon) - $5 each pair
Hollowtop Tire Sandals - $5 or less. Not super easy to make, but they come with a 50,000 mile warranty :)
Pepsi Can Stove - free
Walmart Greasepot - $6
TacoBell Spork - Free
1 liter water bottle - $1.50 or so.
Mora knife 4oz or so - $9 or less - I know there are lighter knives, but for the price, you will not find a better quality knife. It is also fixed blade, which in the event of an emergency situation is HIGHLY desireable.
25ft 550 cord w/ inner core lines- $3
Toss in Vicks coathanger stakes... under 2 oz total. Free.
That list is about $180 or so... and under 10lbs, easily.
Im not sure I missed anything of major significance but I might have. Oh Well.