Does anyone do something like this but fire rated? Or indeed anything a little more interesting than bog standard?

There’s plenty of fire rated downlighters available. No link showing so don’t know if you’ve got something in mind. Robus or Click are two well known manufacturers. A good electrical wholesalers should be able to help.
Rich.

Oops! This sort of thing
http://m.screwfix.com/p/halolite-recessed-satin-silver-3-light-spotlight-240v/42025

Generally, yes, you can get most styles of ‘ordinary’ light in a fire rated equivalent, but only from the ‘better’ manufacturers.
Something like you have pictured above would be around £200 for the fire rated type.

Far cheaper would be to buy fire hoods for whatever fittings you have got. (if allowed by Building Control/whoever is in charge). These are £10 – 40 per fitting, so more economic to buy standard light fittings and fit a hood , of course, this assumes you have room above the light fitting. They stand up around 100mm above the fitting, just like a tent. This gives 30mins to 1 hour of fire rating.
We’ve just done the same in a school, the Spec. called for new fire rated lighting, we gave them the quote, which was £4000+ for 2 classrooms, and the alternative of the hoods at £600. They had the hoods.

Cheers for that. Very helpful. These are to retrofit to an upstairs landing so access from above is no problem and no building regs.