Well I have all the bits now for both sides, just need a nice bit of weather to sort it.
The shock is from Maduggo's supplier, everything else is from Lexus. The spring sits on that huge dust boot (about £60), the orange thing is some kind of bump stop I guess. I wasn't sure about buying the top mount, a circular bit of metal, but it was only £25 or so and it has a big thick rubber collar around the edge, so I thought I might as well as it'll help reduce noise getting into the cab. A new bolt for the shock is a no brainer, the old one will be corroded to hell. Total cost, about £150 for the above, so £300-ish for both sides.