It'll probably be hard to find any because so many of the hmong movie vendors closed their stores after covid hit.
Since you specifically want to watch Xab, I would suggest reaching out to him to see if he has any you can but directly from him that way he makes a direct profit from you too. If not him, then whoever might've produced them you can reach out to them. For example, Kou Thao produced a lot of old ones featuring Xab too, and would sell often at the Milwaukee Hmong New Year so maybe try asking him or if he knows any vendors you can buy from.