Hello John Lee, your server is now in version 9.1 PL 09?
If you should seek B1_SHR folder because within this folder are the Client Installers
Example: \\ [SERVERNAME] \ B1_SHR
Still installers SAP Business One can be found in the SAP standard path (but depends on an S-User with permissions).
https://support.sap.com/software.html?url_id=tile_download_software
To download the package "installation" initial path is
https://support.sap.com/software/installations.html
About the installation package of the 9.1 version it is in PL 05, so if you are already in higher PL will not need it, starting to use only the top PL package.
Thus even for first installation of a new computer that will run as a client, you should use the update package updates are available for download at:
https://support.sap.com/software/patches.html
Which in your case it is the PL 09.
Regards,
Rodrigo da Costa Feula