the software is compatible with GPS receivers that put out standard NMEA sequences.
I have the Randmcnally GPS receiver and copilot 2001 works fine with it.
You can get the GPS receiver on ebay(~$80) or at a randmcnally store ( $99).
The softwarre is another question bc it's not sold separately from the receiver so you are on your own in that aspect
do a search on the forum for copilot and you will find other info.