Knocked my impulse sealer off my table and cracked the knob (part you use to press down) so I modeled this one up. It uses an M5 heat set insert in the bottom then I used an M5 20 (does not need to be that long but it's what I had) up through the bottom and secured the new knob.
Printed mine out of Prusament PLA on my MK3S with raft and it came out perfect.
The author hasn't provided the model origin yet.