UPVC Door Threshold REPAIR QUERY

[MickBee]

The UPVC door in our kitchen (which opens outwards) has a crack in the plastic threshold on the inside. The crack is about 400mm long and gap width is 3mm max.
I have attached some photos showing the detail.
Is it possible to get this repaired? I have tried several firms and at least 3 have declined - two said that it is not repairable. (I'm still waiting for more replies.)
I'd prefer to avoid having to replace the whole frame (which includes a window beside the door) if at all possible.
I'd consider a DIY job but I wouldn't know what material to use that would blend with & adhere to the existing UPVC.
I can't contact the original makers (Diamond Windows of Bristol) as they are no longer in business - door was fitted 19 years ago.
Constructive suggestions welcomed.

 

[Gazman16]

Any repair will likely just crack again next time it get knocked.
I would superglue it and then cover it with a angled aluminum kick-plate/threshold. I think wicks have something that might fit it there shops

 

[MickBee]

Thanks for your helpful reply. The only firm to offer a cosmetic repair want over £300 and then don't guarantee that it will last, so a glue job with a cover strip for strength seems a better idea.
Wickes do a few thresholds - and my excellent local DIY shop Bishopston Hardware have wide selection of strips & angles. (I also found online /www.floorandwallsolutions.co.uk/ who have a wide range of items - I just put this in for anyone else who finds this thread.)
(I had assumed that the door frame was metal with a UPVC coating, but a bit more research suggests that the whole frame is just UPVC, with possibly a bit of reinforcement. As the damaged part is not structural, it seems pointless & wasteful - money & materials - to replace it all.)

 

[Gazman16]

Repair company's do some amazing work but as you say not worth it in this case. If you do ever replace this door or any other make sure you go for the "low aluminum threshold" Less of a trip hazard and wont break like PVC thresholds

 

[crank39]

Pvc thresholds don't break on their own though, stop standing on them!