Convert a Tiger 10.4.11 Addressbook to El Capitan Contacts

My octogenarian parents’ ancient G4 with MacOS X Tiger 10.4.11 finally bit the dust. I was able to retrieve from their Library Folder the Addressbook files from a User account backup but I have been unable to import the Addressbook into El Capitan Contacts. We no longer have a Tiger compatible iMac or, for that matter, a Tiger 10.4.11 installer. Anyone have any thoughts on how to get there contacts back, or anyone have a test machine running Tiger who would be willing to export their Addressbook for us? Help!

I’ve included a screenshot of the files in the G4’s Addressbook folder.