Any second-hand business class laptop that fits your budget, i.e. HP Elitebook/Probook/Zbook, Dell Inspiron/Latitude/XPS, or Lenovo Thinkpad.
Businesses tend to get rid of them after 4 years, even if they’re still in good condition. Great bang for your buck and easily repairable if something does end up breaking.
You’ll have to install Linux yourself, but generally support for older hardware is OK.
IMPORTANT: make sure the BIOS isn’t locked before buying.
You really just need, like, a screwdriver set to get into most laptops. Maybe you can search online (e.g. on YouTube) for tutorials for your model. Then you can buy a replacement fan and also replace the thermal paste, because 13-year-old thermal paste surely isn’t doing you any favors in the performance department. Altogether it shouldn’t cost more than €50 (if you’re careful not to break any internals).
BTW, if you want to watch YouTube videos with less resources, you can also copy the video URL into VLC