With https://twitter.com/rpilocator I've bought 5 4's at retail price over the last month. They are by no means easy to get - but with a little effort they are possible to get. (Unless you need an 8gb one, those seem super rare.)
I found one in England from PiHut and had it shipped here a few months ago. But it was DOA. Their return process is that I have to ship it back and they might refund me for that.
I just ate it. So if anyone wants a Pi 4 w/ 2GB of bad SDRAM lemme know. I may just see if I can reflow the chip to fix. But I’m pretty terrible with hot air + smd, so I’m hesitant.
I really wanted the 4GB model to run monitoring software for my home network, etc. anyway. So I got a RockPro64 and I love that thing.
When I looked you could still get a 3 easily, which would be fine for this. It runs on a teensy too apparently, so it doesn’t seem the 4 helps in any way. Given it runs on a 2 means it’s just 32bit. You can probably still find a 3 easily.
They're so hard to find around here that they're being scaled at $200/pop for the 4s.