I use Binary Eye (f-droid, google play) for qr scanning on my devices.
https://play.google.com/store/apps/details?id=ru.andr7e.deviceinfohw&hl=en_GB&gl=US
Try something like device info hardware to see if it detects the hardware for the camera. If it's not detected then I would suggest it's dead. The fact both the LED and camera have gone suggests something on the motherboard rather than LED/camera modules as they are separately connected.
Which app are you using for your messages? The default one? Have you tried out another one such as Textra or Handcent to ensure it's not an app based issue?
https://play.google.com/store/apps/details?id=com.textra&hl=en_GB&gl=US
https://play.google.com/store/apps/details?id=com.handcent.app.nextsms&hl=en_GB&gl=US
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where can you see that the phone is unlocked, so that I know that any eu sim card works?
Dunno what the shipping would be like, now my idiotic countrymen have made us leave, but I know Amazon UK have the EU version in stock because I bought it recently.