Customizing a message on Record not Found Page

Now the 'contact us' on Record not Found page directs users to support@aha.io, and therefore users without access to certian workspaces:

1. go to Aha! support first

2. Aha! support has to direct the users to the billing admins of our instance.

3. The account admin forward the request to product line owners based on the requested workspace / url access (We delegate user access management to each product line owner)

We need the ability to customize a message on the Record not Found page (similar to the 'new user message' in sso) to provide the contact info of all product line owners. By doing this we are able to streamline the process and direct our users to the right contact in the first place.