You can do this using SharePoint Search. REST API also contains Search APIs for SharePoint.
Create a result source by adding paths of all your lists in the query builder (also specify content type contains item). Check this article for creating a result source.
Your query builder should look like this.
Check if the results are as desired and then you can use the Search API referring to the Microsoft documentation here.
To get results from result source using search rest api, I used the following url
here instead of
querytext='*', you can add your PR NO. For Example,
To build Search Rest API Queries, you can use this free tool -> SharePoint Search Query Tool. This tool is very useful in creating SharePoint Search REST API URLs.