Even with pessimistic assumption of paying 5 billion $ per plant. If Germany had done what France did in the 70/80s they would be much better off now and for the next 100 years. And the cost per plant would be far lower once you start mass production.
If you actually did it right rather then incredibly stupidly, nuclear waste would be a resource for the future, and the idea of disposing it would be utterly ridiculous. Just as with all these idiotic disposal solution that governments like to waste money on. In typical fashion the anti nuclear people first create problems, demand that money is spend on them and then blame nuclear for those problems.
A sensible approach would be have a government fuel bank responsible for securing reserves of nuclear fuel, supplying and recycling nuclear fuel to the nations nuclear fleet. This fuel reserve centrally managed and it controls access to fuel for both commercial operates, research, ESA and so on.
Maintenance of spend fuel is not actually expensive and it places little burden on government to do, even if its for 100s of years. Its literally just a bunch of containers in a warehouse. And that could of course be supported by fees for rate payers.