If you've been all over the internet, perhaps not. However, if you know the brand of toilet, try ebay. I had a plumber break the ceramic tank of a toilet in my home. No new replacements available (26 year old home). Plumbing company offered to replace the entire toilet - with the cheapest one available today that came no where near matching the others in my house. I got on ebay and, wonder of wonders, there are herds of companies there that sell gently used toilet parts.
Had a similar problem myself.