If you require v6 to be static, the ipv6 equivalent to a static IP is a static /64 subnet, aka, an entire LAN. Since it’s globally routable, it needs to be issued by an RIR, the same way an IPv4 address would be.
So yes, they would issue it.
If they don’t have facilities for ipv6, there are options, such as getting an ipv6 over IPv4 tunnel going with someone like he.net. such tunnels add complexity and more work to the set up and rely on you having a very flexible router, but can be a good alternative.