internal supplier registration bank account field

Summary:

Hi Experts - My customer is having an issue that sometimes the correct bank branch number may not be available in the data tables when submitting an internal supplier registration request (since it's a NEW supplier) and they are not able to move forward with the registration without having a bank branch selected. Bank Branch Number populates both the bank and branch fields.

is there a way to add an "Other" option in either the branch number or bank branch field on the Internal Suppler Registration form and then have an open text field pop up to populate the details? or any other work around?