On Sat, 26 Jan 2019 19:36:14 +0000
ss wrote:

Re previous post:
Ok having looked at it more carefully I have managed to seperate the
2 parts (also better images below) It is off a Kirby vacuum shampoo
water tank, it is an on/off `valve`
My thoughts are to insert a couple of pins (dovetail layout) to
support whatever epoxy will stick to the plastic and fill the void at
the bottom left hand image.
There is no reason to have to disassemble this part later on so a
permanent fix I am hoping for.

Any further thoughts welcome?

https://imgur.com/a/IlPyXtY

Remove the remaining tab and clean up the surface. Get a bit of
square steel bar (door knob spindle?) heat it up and press it in so it
makes a socket for itself. Assuming this is a thermoplastic you're
dealing with, of course.