CG-NAT traversal options

I am in the process of changing ISPs at one of my sites with a KiwiSDR that is open to the public. The new ISP utilizes CG-NAT so traditional port forwarding at the router is no longer an option. Looking for a free or inexpensive (<$100/year) pathway to do this. At the moment I can cobble together a solution involving the free ngrok service to a PC, combined with routing to the Kiwisdr. But that is rather tedious to maintain, since the route expires every time I reboot the PC or there is a power outage. I'm sure this NAT traversal is a common problem (and maybe it's already been "solved" in this forum), so curious to hear how others have dealt with it. As an aside I have been delighted with the free mesh VPN from tailscale.com, useful for remotely accessing a variety of remote things in my world.