NAS/server component recommendation

Hello, i'm looking to upgrade my 10 years old NAS/server. I already have the HDD and the case. But i have difficulties to chose motherboard, power supply, CPU & RAM.

So far i'm looking for :

• AMD CPU, +12 threads
• A bunch of SATA ports, maybe a LSI ? Which one ? And 2 NVME slots for the Motherboard.
• More than 16GB of ram, IF possible ECC
• All of this available in western Europe

I'm aiming for a budget between 600€ and 900€ for those 4 components.

Have a nice day :)