Multiple host names per network interface

First time posting :)

ACME SBC 3900 HA pairs

I've configured Teams direct routing for my US subscribers and now that my Canadian ATT trunks are up, I need to separate Canadian callers from the US callers so their outgoing calls can route to the correct trunks. For another Teams SBC (PSTN Gateway) for Canada, I need a new FQDN/hostname for the Teams Canadian routing. Unfortunately all my physical interfaces are used up, and I only have the one DMZ subnet, so i cannot VLAN the network interface on the same subnet. I'm looking for best practice here to add another host name for a new address on the