Yes you can do this. You can install a second instance of SSRS (SSRS supports named instances) on the servers. You will probably want to point this at a new ReportServer database so that it’s totally separate.
You’ll need to assign the SSRS servers another IP so that the sites don’t conflict with each other, unless one is HTTP and the other HTTPS.
You can probably just point it to your existing SSRS farm and be done with it. Just setup an SSL cert on the sites in the existing farm.