I'm planning a 26" build for my son who is making his current 24" look a bit small, but finding tyres is a tricky one. My usual standard would be a tubeless Racing Ralph for the riding he does, but they appear to be silly money now. bikediscount has the basic folding Rocket Ron for €25 but not designated tubeless, with enough sealant that should do the trick though. Any better ideas for 26" wheels these days?
I found some mavic quests for peanuts, IIRC £7 each, they're really pretty nice.
Try a (stealth) wanted ad on here? Judging by the prices of some of the 26" bikes being offered here and on ebay these days, prices are loooow. I would have thought there are tons of slightly used tyres kicking around in sheds nationwide available for £cockall.
https://www.on-one.co.uk/i/q/TYGEBAUST/geax-barro-mountain-ust-tubeless-tyre
Cheap but I've not used them myself.