Good evening
I actually had the same question a few days back.
So, at least in Germany I found a few.
There is the Sharkoon Pure steel for roughly 60€
And there are two Silverstone cases, the Raven RV04 and the Fortress FT04, the Raven only costing roughly 60€ as well.
Those where the cheapest new ones I could find- both Silverstone cases may be not the newest ones but they are both ventilated very well.