Reloading is the answer of course.It's a very interesting cartridge but only one manufacturer of it. I believe it's only PPU and they only do limited supply runs. Part of the enjoyment of owning such a rifle would be the enjoyment of shooting it. And unfortunately that keeps the demand down when you can't get ammunition either.
But reloading is also becoming more expensive. A good friend of mine just spent four hundred dollars on powder. And it wasn't a large amount either. I personally would like to shoot more 11mm mauser. Unfortunately, I can't get the brass cases.Reloading is the answer of course.
Same with all obsolete calibers.