Which hardware for a firewall?

Hi all,

I'm going to create a firewall with openBSD, and would like to use the
ARM64 or ARMv7 distribution for that. Unfortunately I don't know what
hardware I can get for this, and that's the reason for this mail. Can
someone point me to a suitable platform for this? If this email does not
belong on this mailing list, I offer my apology. This is my first post
on this mailing list, and ask for understanding. Sincerely, Karel.