LandSAR - where you end up carrying your gear, enough gear for the person who doesn't have enough gear of their own, and some backup gear for when the gear you loan them needs to be used by someone else in the team who forgot their gear.
I am picking you will already be getting drilled on this - but multiple torches. Headlamp, handlamp and a spare torch to give to someone else. Get some of the reflective tape to wind around the torches - having watched a couple people drop black torches in the bush - a bit of a reflection helps when trying to find things.
Second the notion of a bivy bag over those survival blankets - especially if it's you having to sleep under/in one.
The thing you need to remember - it's possible you will come across someone with fuck all of their own stuff on them. If you need to wrap them up to shelter and keep them warm - you then need something for yourself. A two person tents (or three) suddenly makes a lot more sense.
One thing I found immensely useful (warning - about to plug a product I sell) - are the RIBZ Packs. One you get issues a harness/radio it's not as viable - but I found I could carry all my survival gear, maps, and and tracking gear in the one pack. The 'Alpine Orange' also gives you a bit more colour in the bush. RIBZ Front Pack - GEARLOCKER
Big, heavy duty rubbish bags. Like the MSC survival bags. Multiple uses, and for putting, well, things, you may find in the bush into.
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