Data Sharing / Roles and Search Result

Data Sharing / Roles and Search Result

Hi,

I want to setup the following customization, but cannot figure it out:

I do have internal and external sales persons.
The external staff should only see and edit their own leads. Everything fine till here.

In the case the external sales staff searches for a lead that has not been crated by their peer group (so they normally would not see it) only the full name and company, as well as the lead owner should be displayed as a search result.
the intention is to give every user an overview if a lead is already existent in the system and who´s owning it, but they should not access the full dataset of the lead.

Is this setup possible?
I´m aware about the Profiles, Roles and Field&Links Permissions but couldn´t figure out how to setup this specific scenario.

Thanks in advance,
Frank