This Chillblast is slightly over budget but not hugely so.
https://www.chillblast.com/chillblast-fusion-gulfstream-x-plane-flight-sim-pc-designed-by-momedia.html?category_id=672

• Processor: Intel Core i5-9600K CPU, 6 Cores / 6 Threads, 3.7 - 4.6GHz
• Overclocking: Overclock my CPU by up to 20%
• Case: NZXT H510 Tempered Glass Case - White
• CPU Cooler: Corsair Hydro H100i RGB PLATINUM CPU Cooler
• Thermal Paste: Standard Thermal Paste
• Motherboard: Asus ROG STRIX Z390-F GAMING Motherboard
• Memory: 16GB G.Skill Trident Z RGB DDR4 3200MHz Memory
• Graphics Card: NVIDIA GeForce RTX 2060 Super 8GB Graphics Card
• OS Drive: 500GB Samsung 970 EVO PLUS M.2 PCIe Solid State Drive
• Hard Drive: Seagate 2TB BarraCuda 7200RPM Hard Disk
• Optical Drive: None
• Power Supply: Corsair RM750x 80 PLUS Gold 750W PSU
• Sound Card: Onboard High Definition Audio
• Operating System: Windows 10 Home 64-bit
• Anti Virus Software: Bullguard Internet Security - Free 90 Day Licence
• Warranty: 5 Year Warranty, 2 Years Collect & Return UK only

With your budget you're limited to one SSD and only 8Gb graphics card but those can be replaced in the future. You can choose a different case. Memory is by GSkill which is deemed better than Corsair. The CPU can be swapped for a i7-9700 for another £100.

My own was from them and they're a quality company.

Thank you @Ray Proudfoot for your help! 

@Danegan4321, sorry about the price. I'd forgotten about GBP versus Euro.