easiest way to replace my suitcase handle

Remove the screw. Stick a nut and bolt with washer on each side of the handle. Job done

It's hard to tell where it's broken from those photos.

The 'screws' have hex heads which look likely to be much deeper than the gap between the plastic and the metal suggesting they're not sandwiching the metal between the head and plastic as you'd normally expect from a screw.

Are they acting as pegs, filling the circular holes to prevent movement? If that's the case then the holes don't appear to be greatly distorted or the metal tube overly bowed out so I wonder if there's a crack in the plastic part of the handle allowing the pegs to push inwards?

Looking at the fixing that is hanging out of the fixing hole:
it appears to have some material attached to it, possibly plastic from the plastic inverted U handle (or does the plastic handle have a metal insert containing the fixing aperture?), so not convinced a simplistic "just fit a new fixing/screw" will solve the problem.

Probably best to remove all fixings to expose the entire inverted U handle, then either reinstate/rebuild the missing material,
or add insert,
or some other solution compatible with the fixing design, where the design is currently hidden by the vertical metal section of handle.

Or if less than 5 years since purchase:
contact Tripp to exercise the brand's hilarious 5 year warranty - but brace for disappointment
tripp.co.uk/qui…tee