Aqui está uma solução de software (20 dólares ou menos, se você comprar mais licenças):
DOS2USB : captura o trabalho de impressão do MS-DOS de qualquer LPT ou PRN e redireciona-o para a impressora USB , Impressora GDI, impressora de rede, etc.
DOS2USB extends the printing ability of DOS programs by capturing MS-DOS print jobs and redirecting them to windows printer irrespective of Printer types including USB Printers, Network Printers, Print-Servers, and PDF-printers. The job redirection works even if a printer is physically connected to the captured port, on any PC running Windows 95, 98, ME, NT, 2000, XP and 2003 (With Terminal Service Support).