Is it possible to limit the LOV for the First Approver in the Payment Process Request page?

We have created a Payment Process Request Template and selected the First Approver in the Payment and Processing Options. This can be overridden during PPR submission.

The LOV is showing all employees, is it possible to limit the list to a few employees only? If yes, how?

Note that our Payment Approval Rules is using the First Approver in the workflow, thus we need the list to be limited.