Hello Greg,
I would suggest to modify the transformation which you are using for displaying the search results. In this transformation you should just replace the current domain with the domain you need. If you are using ASCX transformation, you could simply create custom method as described here https://docs.kentico.com/display/K81/Adding+custom+methods+to+transformations. In case you are not using ASCX transformation, then you could implement custom macro method. More information could be found here https://docs.kentico.com/display/K8/Registering+custom+macro+methods
Regards,
Roman Konicek