As part of the refurbishment of my elderly relative's bungalow prior to putting it on the market, I'd like to replace the tatty, chipped front door handle. There's a picture at
The uPVC door was fitted something like fifteen years ago by a local firm long since extinct (though I imagine they bought in their windows and doors) so is it feasible to replace just the handle? There seems to be a single grub screw on the underside of the boss (if that's the right term) so I'm hoping that it's simply screwed to a straight-through spindle, but I'm mildly reluctant to remove without more definite knowledge in case the whole thing falls apart.
Many thanks.