Custom made orthodontic retainer worth the money?

[NavySalt]

I had Invisalign treatment some time ago and now bound to wear an upper retainer for all my life. My current one was destroyed by DD. I was just thinking shall I get one online? It is 50£. The one where they send you a kit first to make the inprints and then the retainer. Are they any good? Or do I need to try and get a real appointment? Cannot contact my doctor, they are abroad.
Does anyone know what the difference in price would be?

I'd only use it as a temporary one, get a dentist to make another as it's not the risk of messing up your teeth

I had to get a replacement retainer at an orthodontist and it was about £90 I think? This included everything so moulding trays and 2 appointments (one to do the mould and one to check the fitting).

They also repaired my fixed retainer too when it broke a bit. This was a new orthodontist as I'd moved several years after having Invisalign. I asked my dentist to recommend someone and they were happy to help.

Oh thank you! I will call the local orthodontist to book an appointment