BMW X5 2011 E70 engine issue

[EdonP]

Hi, I am having an issue with my X5 however haven't been able to send it to a mechanic yet due to it being the weekend and no one being around. I will try to explain my issue as much as I can. While driving yesterday I had stopped at a place and my vehicle shut off, for about 3-5 minutes it wouldn't start and after it did I started hearing what I could only describe as a knock from my vehicle. From the videos I have sent to a few mechanics they told me it most likely is the connecting rod and the crankshaft, and as such the whole engine needs to be replaced. Would there be a chance to only replace the connecting rod and crankshaft since I believe the engine was saved without much damage, if I absolutely need to replace the engine what would be the best place to buy a new one? [Europe] Appreciate the help!