Honestly, a static site that accepted pull requests would cost nothing. Free code hosting on GitHub and page hosting on GitHub Pages or Cloudflare Pages. Literally $0, forever.
It does take time and effort to review pull requests, but there are no $ costs involved.
On the other hand that's a really easy way to handle the community updating the listing. Generate a static page from text files, use PRs to add entries to the text files.
It does take time and effort to review pull requests, but there are no $ costs involved.