tell application "Printer Setup Utility"
set currentPrinter to (path to library folder from user domain as
Unicode text) & "Printers:" & name of current printer & ".app"
set currentPrinter to (path to "impr" as Unicode text) & "Printers:"
& name of current printer & ".app"
end tell
The first syntax use only official objects.
The second one use a definition given in "Folder Manager Interfaces".
I am not sure that it would be perfectly safe.