The JetKVM is very impressive looking at a great price. Until recently it wasn't really available in the US but it looks like it is now/
The V4 Mini is a very nice piece of hardware. I paid $300 for one in April from Amazon. I also got PiKVM running on a Pi Zero 2 W and it worked fine but was a bit squirrely. Having the purpose-built device is nice.
You can also use a Pi Zero 2 W as a serial console: it has a USB On-the-Go port perfect for the purpose. But the KVM approach is more generally useful since you can access a consumer BIOS from it.
They recently opened a global store. Previously, the only way to get one was to "buy" it on kickstarter, presumably from the US as well as the rest of the world.