.NET 6 Blazor Server routing with URL Rewriting?

Question

I have a problem, I have an older asp.net webforms app which I'm trying to convert into a Blazor Server app. The issue that I'm running into is with the url routing. I'm trying to do something like this within my razor page

@page "/{param}-items-for-sale.html"

blazor doesn't like this, I have tried to make use of the .net Core URL Rewriting module and doing this will allow me to rewrite the url but then it causes a problem with the SignalR connection and it ends up going to a page not found error.

Is there a way for me to route urls like this in my blazor app as I have many many pages which have already been indexed within the Search Engines and it would become a big issue if I had to change the format of the urls globally.

thanks in advance.