Assuming a compatible phone and a compatible carrier (AFAIK AT&T and Verizon both still operate white lists), no there's nothing stopping you. There are/were US users who bought Sailfish over VPN. But for official hardware at least, "compatible phone" is the sticking point. The last phone with a North American variant was the Sony XA2 from early 2018. Today it's a brick because Jolla never gave it VoLTE support.
