have you tried doing this with the macro recorder? Turn on the recorder, give the macro a name (no spaces allowed). Select the printer, print, then Stop Recording.

To add a button to a toolbar: View > toolbars > customize. Go to the middle tab I forget what it is called. In the left pane, scroll to find Macro. In the right-pane, see your macro name. Drag this button to a toolbar. You can use the Modify Selection button to Change Button Image.

Sorry I am on a different version and saying this from memory.

Repeat the process for the other printer.

Sorry I am not able to test this at this time. Hope it works.