How to dismantle tap, kitchen mixer, ceramic

[snowhead]

There are plenty of online sellers for Ceramic spares if you can't get one locally;
Replacement Brass Valve Ceramic Disc Cartridges - Plumbers Mate Ltd

 

[Welder]

Yours looks like a 28 spline.
Make sure you measure the seat depth properly from the underside of the shoulder to the very end of the red seal. That is VITAL.
Try the LUNNS website.

 

[Welder]

There are plenty of online sellers for Ceramic spares if you can't get one locally;
Replacement Brass Valve Ceramic Disc Cartridges - Plumbers Mate Ltd

Ouch 🙁🙁🙁