>>2703906>Sleeping bag:MacPac still make good sleeping bags and they're regularly on sale. Available in UK last time I was there, but if there's anything you could safely order online it's a sleeping bag.
It's not on your list, but if you're looking for a shell to last forever, check out the Cactus Outdoor mountain jacket.
Probably a leap of faith because you'll almost certainly have to order online, but the guys there are really helpful - just explain where you are and ask what the fit is similar to in a more common brand. They make the most bomb-proof gear available right now.
>ChairYou don't need a chair. If you must have something, just get one of these to stick your sleeping mat in - it's not like you can use both at the same time, so why carry extra crap?
https://www.macpac.co.nz/macpac-standard-serac-1000-down-sleeping-bag-%28-17%C2%B0c%29/120063.html?dwvar_120063_color=Cherry%20Tomato&dwvar_120063_clearance=no#srule=Sort-By-Price-Desc&start=2&sz=12 