Have you considered making the property specific to the host being deployed to and using the property assigned to the target instead of the source? Otherwise a unique name for the property per deployment, but that might make the dictionary grow quickly and require tweaking of the properties used in the package for each deployment.
Just some brainstorming...
are you executing the job via a blpackage? or is it an nsh script? or a perl script? can't you just keep this information in an external db table, and access it via a script?