While I'm pretty sure that it can run on a small budget, I'm less sure that the owners have the time to maintain the site (a static website still needs to update the server, domain and certificates and while this can be automated to a degree it's still a lot a work).
If they are static sites and mostly text, they could be hosted directly out of freaking S3 for a pittance. There is no way a service this niche and this intentionally minimal consumes enough bandwidth to make that painful.