It's basically impossible to get any Pis these day - we were able to score a bunch of Pi Zero W so that's what we're including for now, but it's fully compatible with any 'zero' form factor SBC.
I hear your pain, I’ve been trying to get a zero 2W for a reasonable price for almost 3 years now. It’s so disappointing how it’s still an issue today.
Super tempted to try one of these out since I run my own synapse anyway. Paired with tailscale running, I could do a lot with it on the fly but probably would need a Zero 2W to handle everything I’m imagining.
Works great with your own synapse too!