Sentinal-C Hardlock

[Davidlee48]

I have an old DOS program, still in use at my company. We have been using a licensed copy since around 1992. The company we got it from went out of business in 1995, and the company that bought them out no longer has licensing info available. I did manage to copy the install software from the original 5 1/4 disks, onto 3 1/2 disks. We have the original parallel dongle (hardware lock) but would like to try to emulate it, somehow. The computer it is on has been updated to Win 2000, but we are worried about how long it will continue to run. Is there any way to emulate the lock? It is a Rainbow Sentinal-C, Version A. I have the numbers noted, or could use something to read it, if I knew what to use.
Any help would be appreciated. Thanks.