There are several versions of CrossDos that were written. There is an early version of CrossDos incorporated in AmigaDos v3+ and a much better version (CrossDos Gold) that was released in the mid 1990s). I don't know of anyone still selling a copy but you might get lucky with Software Hut, etc...
Copies of CrossDoss still turn up on eBay from time to time.
Regards,
Ltstanfo
